Heat transfer fluids, methods and systems

ABSTRACT

A heat transfer fluid including 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB) for high temperature heat transfer applications and environmental and safety requirements, which is non-flammable (and has no flash point below 100° F.), has low toxicity, an ODP of &lt;0.01 and a GWP of 44, is dielectric and electrically stable.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Application Nos. 62/784,020, filed Dec. 21, 2018, 62/784,035, filed Dec. 21, 2019, 62/784,041, filed Dec. 21, 2019, and 62/784,049, filed Dec. 21, 2019, all of which are herein incorporated by reference in their entireties.

FIELD

The present invention relates to methods and systems for removing heat from and/or adding heat to operating electronic devices and systems, to thermal management of such operating electronic devices and systems, and to other high temperature heat transfer applications like secondary loop systems, organic Rankine cycle (“ORC”) applications, and high temperature heat pumps.

BACKGROUND

Heat dissipation is becoming an increasingly challenging issue in many applications. In portable and hand-held electronic devices, for example, the desire to miniaturize while adding functionality increases the thermal power density of the device while in operation, thus making cooling of the electronics components, including the batteries, within them more challenging. As computational power increases within desktop computers, datacenters and telecommunications centers, so too does the heat output, again making thermal management of such electronic devices increasingly important. The acceleration of electrification of mobility also presents new challenges for thermal management (e.g., cabin, battery in electric vehicles). In electronic vehicles the thermal management function is especially important for several reasons, including the criticality of cooling the batteries within a relatively narrow temperature range and in a way that is reliable, efficient and safe. The challenge to provide effective thermal battery management is becoming greater as the demand for battery-operated vehicles with greater range and faster charging increases.

The efficiency and effectiveness of batteries, especially the batteries that provide the power in electronic vehicles, is a function of the operating temperature at which they operate. Thus, a thermal management system must frequently be able to do more than simply remove heat from the battery during operation and/or charging—it must be able to effect cooling in a relatively narrow temperature range using equipment that is as low cost as possible and as light weight as possible. This results in the need for a heat transfer fluid in such systems that possesses a difficult-to-achieve combination of physical and performance properties. Furthermore, in some important applications the thermal management system must be able to add heat to the battery, especially as the vehicle is started in cold weather, which adds further difficulty to the selection of heat transfer fluids for use in such systems.

One frequently used system for the thermal management of electronic vehicle batteries involves immersing the battery in the fluid used for thermal management. Such systems add the additional constraint that the fluid used in such systems must be electronically compatible with the intimate contact with the battery, or other electronic device, while the battery or device is in operation. In general, this means the fluid must not only be non-flammable, it must also have a low electrical conductivity and a high level of stability while in contact with the battery or other electronic component while the component is operating and at the relatively high temperatures existing during operation. Applicants have come to appreciate the desirability of such properties even in indirect cooling of operating electronic devices and batteries because leakage of any such fluid may result in contact with operating electronic components.

The thermal management fluid which has been commonly used for battery cooling, including immersive cooling, is a water/glycol combination, although other classes of materials, including chlorofluorocarbons, fluorohydrocarbons, chlorohydrocarbons and hydrofluoroethers, have been mentioned for possible use. See, for example, US 2018/0191038.

While many fluids comprising compounds in the above-noted classes, including fluorohydrocarbons, have been used or suggested for use as refrigerants generally, those skilled in the art of thermal management of operating electronic devices will appreciate that many, if not most, of the fluorohydrocarbons will not satisfy the fully compliment of desirable properties to be effective for use in cooling of operating electronic systems, especially for immersive cooling techniques. For example, U.S. Pat. No. 5,026,499 discloses an azeotrope composition comprising fluid comprising 21-27 wt. % of 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB), 64-72 wt. % trans dichloroethylene and 5-11 wt. % methanol and suggests that such a fluid generally for a solvent, an aerosol, a blowing agent and a refrigerant. However, there is no disclosure in U.S. Pat. No. 5,026,499 mentioning or suggesting use of such an zeotropic composition in the specialized methods and systems according to the present invention, as describe in more detail hereinafter.

Thus, applicants have come to appreciate the need for thermal management methods and systems which use a heat transfer fluid which is environmentally acceptable, non-flammable, has low or no toxicity, has excellent insulating properties and has thermal properties that provide effect cooling and/or heat of operating electronic components in a relatively narrow temperature range with equipment that is low cost, reliable and light weight. Thus, for example, applicants have found that fluids that have relatively low boiling points (e.g., below 50° C.) are not desirable in many applications since the use of such fluids will tend to increase the cost and/or weight of the cooling equipment for many battery and/or electronic cooling applications, and may also decrease reliability, as explained hereinafter.

The Rankine cycle is the standard thermodynamic cycle in general use for electric power generation. The essential elements of a Rankine cycle system are: 1) a boiler to change liquid to vapor at high pressure; 2) a turbine to expand the vapor to derive mechanical energy; 3) a condenser to change low pressure exhaust vapor from the turbine to low pressure liquid; and 4) a pump to move condensate liquid back to the boiler at high pressure.

Various working fluids have been suggested as working fluids in Rankine cycles, including HFC-245fa. However, there is a desire in the industry to provide a working fluid which is environmentally acceptable, has excellent thermodynamic properties, and can operate efficiently over a wide range of heat source temperatures, including, for example, at least about 200° C., for example of from about 200° C. to about 400° C.

There is also a desire in the industry to provide a heat transfer fluid (e.g. a refrigerant) which is environmentally acceptable, has excellent thermodynamic properties, and is non-flammable.

SUMMARY

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by evaporating at a temperature greater than about 50° C., greater than about 55° C., or greater than about 60° C., a heat transfer fluid comprising, consisting essentially of, or consisting of 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB).

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by evaporating a heat transfer fluid comprising at least about 50% by weight of TFMCB.

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by evaporating at a temperature greater than about 50° C., greater than about 55° C., or greater than about 60° C., a heat transfer fluid comprising at least about 50% by weight of TFMCB.

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by evaporating at a temperature greater than about 50° C., greater than about 55° C., or greater than about 60° C., a heat transfer fluid consisting essentially of TFMCB.

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by evaporating at a temperature greater than about 50° C., greater than about 55° C., or greater than about 60° C., a heat transfer fluid consisting of TFMCB.

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by adding sensible heat to a heat transfer liquid at a temperature greater than about 50° C., greater than about 55° C., or greater than about 60° C., said heat transfer liquid comprising, consisting essentially of, or consisting of 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB).

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by adding sensible heat to a heat transfer liquid comprising at least about 50% by weight of 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB).

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by evaporating at a temperature greater than about 50° C., greater than about 55° C., or greater than about 60° C., a heat transfer fluid comprising at least about 50% by weight of 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB).

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by adding sensible heat to a heat transfer liquid at a temperature greater than about 50° C., greater than about 55° C., or greater than about 60° C., said heat transfer liquid consisting essentially of 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB).

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by adding sensible heat to a heat transfer liquid at a temperature greater than about 50° C., greater than about 55° C., or greater than about 60° C., said heat transfer liquid being non-flammable and consisting essentially of 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB) and having a dielectric constant of less than 30 (<30) and an electrical conductivity of less than 15 nS/cm (<15 nS/cm).

The present invention includes methods for removing heat from an article, device or fluid comprising:

(a) providing a high temperature heat source; and

(b) removing heat from said high temperature heat source by evaporating at a temperature greater than about 50° C., greater than about 55° C., or greater than about 60° C., a non-flammable heat transfer fluid consisting essentially of TFMCB and having a dielectric constant of less than 30 (<30) and an electrical conductivity of less than 15 nS/cm (<15 nS/cm).

The present invention also includes methods for removing heat from, and optionally adding heat to, an operating electronic device, including particularly a battery, comprising:

(a) generating heat by operating said electronic device; and

(b) removing at least a portion of said generated heat of operation by transferring said heat to a heat transfer fluid comprising, consisting essentially of, or consisting of TFMCB.

As used herein, the term “operating electronic device,” and related word forms means a device, or a component of a device, which is in the process of performing its intended function by receiving, and/or transmitting and/or producing electrical energy and/or electronic signals. Thus, the term “operating electronic device” as used herein includes, for example, a battery which is in the process of providing a source of electrical energy to another component and also a battery which is being charged or recharged.

The present invention also includes methods for removing heat from, and optionally adding heat to, an operating electronic device comprising:

(a) generating heat by operating said electronic device; and

(b) maintaining said operating electronic device immersed in a heat transfer fluid comprising, consisting essentially of, or consisting of TFMCB.

The present invention also includes methods for thermally regulating the temperature of battery comprising:

(a) providing the battery in thermal contact with a heat transfer fluid comprising, consisting essentially of, or consisting of TFMCB;

(b) providing a secondary fluid or an article other than said battery for removing heat from said heat transfer fluid; and

(c) providing a secondary fluid or article other than said battery for adding heat to said heat transfer fluid, wherein said secondary fluid or article of step (b) may be the same or different than the secondary fluid or article of step (c).

The present invention also includes a thermally regulated battery comprising:

(a) a surface of the battery which will contain at least a portion of the heat generated by the battery during operation;

(b) a heat transfer fluid in thermal contact with said surface, said heat transfer fluid comprising, consisting essentially of, or consisting of TFMCB.

As used herein, the term “thermal contact,” and related forms thereof includes direct contact with the surface and indirect contact though another body or fluid which facilitates the flow of heat between the surface and the fluid.

Applicants have unexpectedly discovered that TFMCB not only meets the challenging performance requirements for high temperature heat transfer applications and for electronic cooling but also satisfies exacting environmental and safety requirements. Specifically, applicants discovered that TFMCB is non-flammable (and has no flash point below 100° F.), has low toxicity, an ODP of <0.01 and a GWP of 44, and is dielectric and electrically stable. In particular, applicants have determined that TFMCB has a measured dielectric constant of 20 at 22° C. as determined by ASTM D2477-07 and has a measured electrical conductivity of less than 10 nS/cm at 22° C. as determined by ASTM D 2624.

The present invention includes also heat transfer compositions comprising at least about 50% by weight of, and consisting essentially of, TFMCB and at least one co-heat transfer fluid component that does not lower the boiling point below about 50° C., below about 55° C., or below about 60° C.

The present invention includes also heat transfer compositions comprising at least about 50% by weight of, or consisting essentially of, TFMCB and at least one co-heat transfer fluid component that does not lower the boiling point below about 50° C., below about 55° C., or below about 60° C. and which does not raise the electrical conductivity of the heat transfer composition above 15 nS/cm at 22° C.

The present invention includes also heat transfer compositions comprising at least about 50% by weight of, or consisting essentially of, TFMCB and at least one co-heat transfer fluid component that does not lower the boiling point below about 50° C., below about 55° C., or below about 60° C. and which does not result in a dielectric constant for the heat transfer composition that is below about 30.

The present invention includes also heat transfer compositions comprising at least about 50% by weight of, or consisting essentially of, TFMCB and at least one co-heat transfer fluid component that does not make the heat transfer composition flammable.

The present invention includes also heat transfer compositions comprising at least about 50% by weight of, or consisting essentially of, TFMCB and at least one co-heat transfer fluid component that does not make the heat transfer composition toxic.

The present invention includes also heat transfer compositions comprising at least about 50% by weight of, or consisting essentially of, TFMCB and at least one co-heat transfer fluid component, provided that said at least one co-heat transfer component is of a type and present in an amount that does not: (i) lower the boiling point of the heat transfer fluid below about 50° C., below about 55° C., or below about 60° C.; or (ii) result in a dielectric constant for the heat transfer composition that is below about 30; or (iii) make the heat transfer composition flammable; or (iv) make the heat transfer composition toxic. Applicants believe that, in view of the teachings contained herein, the selection of the co-heat transfer fluid and the amount thereof can be made by those skilled in the art without undue experimentation.

For example, the heat transfer fluid of the present invention may additionally include at least one co-heat transfer component selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, methanol, ethanol, perfluoro(2-methyl-3-pentanone), cis-HFO-1336mzz, trans-HFO-1336mzz, HF-1234yf, HFO-1234ze(E), HFO-1233zd(E), and HFO-1233zd(Z).

The heat transfer may have a Global Warming Potential (GWP) of not greater than about 1000.

The heat transfer fluid may be a class 1 refrigerant, a class A refrigerant, or a class A1 refrigerant.

The heat transfer fluid may have a flash point of greater than about 100° F. (37.8° C.).

The invention further discloses a heat transfer composition comprising the heat transfer fluid and a lubricant. The lubricant may be present in an amount from about 5% to about 30% by weight of heat transfer fluid. The lubricant may include at least one lubricant selected from the group consisting of polyol esters (POEs), poly alkylene glycols (PAGs), polyalkylene glycol oils, polyvinyl ethers (PVEs), and poly(alpha-olefin)s (PAOs). The lubricant may include at least one polyol ester (POE).

An electronic device may include the heat transfer fluid, and a method of heating or cooling may use the heat transfer fluid. A heat transfer system may include the heat transfer fluid, wherein the heat transfer system may be a vapor compression system including an evaporator, a condenser and a compressor in fluid communication.

In another form thereof, the present invention provides a method for converting thermal energy to mechanical energy in a Rankine cycle, the method including the steps of: i) vaporizing the heat transfer fluid with a heat source and expanding the resulting vapor; and ii) cooling the heat transfer fluid with a heat sink to condense the vapor. The heat source temperature may be from about 90° C. to about 800° C. or the heat source temperature may be from about 90° C. to about 1000° C.

“Global Warming Potential” (hereinafter “GWP”) was developed to allow comparisons of the global warming impact of different gases. It is a measure of how much energy the emission of one ton of a gas will absorb over a given period of time, relative to the emission of one ton of carbon dioxide. The larger GWP, the more that a given gas warms the Earth compared to CO₂ over that time period. The time period usually used for GWP is 100 years. GWP provides a common measure, which allows analysts to add up emission estimates of different gases. See Intergovernmental Panel on Climate Change (IPCC) 5^(th) Assessment Report (AR5), 2014. TFMCB has a GWP of 44 as calculated from the atmospheric lifetime and radiative efficiency (Reference for procedure: Hodnebrog, Etminan, Fuglestvedt, Marston, Myhre, Nielsen, Shine, Wallington “Global Warming Potentials and Radiative Efficiencies of Halocarbons and Related Compounds: A Comprehensive Review” Reviews of Geophysics, 51, 2013. DOI: 8755-1209/13/10.1002/rog.20013.

LC₅₀ is a measure of the acute toxicity of a compound. The acute inhalation toxicity of a compound can be assessed using the method described in the OECD Guideline for Testing of Chemicals No. 403 “Acute Inhalation Toxicity” (2009), Method B.2. (Inhalation) of Commission Regulation (EC) No. 440/2008. TFMCB has an LC₅₀ of >19.15 mg/L.

The flash pint of a thermal management fluid refers the lowest temperature at which vapors of the liquid will keep burning after the ignition source is removed as determined in accordance with ASTM D3828. Thermal management fluids which do not have a flash point below 100° F. (37.8° C.) are classified as “non-flammable” in accordance with NFPA 30: Flammable and Combustible Liquid Code.

“Non-flammable” in the context of a thermal management composition or fluid means compounds or compositions which are determined to be non-flammable. The flash point of a thermal management composition or fluid refers the lowest temperature at which vapors of the composition will keep burning after the ignition source is removed as determined in accordance with ASTM D3828. Thermal management compositions or fluids which do not have a flash point below 100° F. (37.8° C.) are classified as “non-flammable” in accordance with NFPA 30: Flammable and Combustible Liquid Code.

The phrase “no or low toxicity” in the context of a refrigerant composition is classified as class “A” by ASH RAE Standard 34-2016 Designation and Safety Classification of Refrigerants and described in Appendix B1 to ASHRAE Standard 34-2016.

In the context of a refrigerant composition, a compound or composition which is non-flammable and low or no-toxicity would be classified as “A1” by ASHRAE Standard 34-2016 Designation and Safety Classification of Refrigerants and described in Appendix B1 to ASHRAE Standard 34-2016.

“Capacity” is the amount of cooling provided, in BTUs/hr, by the refrigerant in the refrigeration system. This is experimentally determined by multiplying the change in enthalpy in BTU/lb, of the refrigerant as it passes through the evaporator by the mass flow rate of the refrigerant. The enthalpy can be determined from the measurement of the pressure and temperature of the refrigerant. The capacity of the refrigeration system relates to the ability to maintain an area to be cooled at a specific temperature. The capacity of a refrigerant represents the amount of cooling or heating that it provides and provides some measure of the capability of a compressor to pump quantities of heat for a given volumetric flow rate of refrigerant. In other words, given a specific compressor, a refrigerant with a higher capacity will deliver more cooling or heating power.

“Coefficient of Performance” (hereinafter “COP”) is a universally accepted measure of refrigerant performance, especially useful in representing the relative thermodynamic efficiency of a refrigerant in a specific heating or cooling cycle involving evaporation or condensation of the refrigerant. In refrigeration engineering, this term expresses the ratio of useful refrigeration or cooling capacity to the energy applied by the compressor in compressing the vapor and therefore expresses the capability of a given compressor to pump quantities of heat for a given volumetric flow rate of a heat transfer fluid, such as a refrigerant. In other words, given a specific compressor, a refrigerant with a higher COP will deliver more cooling or heating power. One means for estimating COP of a refrigerant at specific operating conditions is from the thermodynamic properties of the refrigerant using standard refrigeration cycle analysis techniques (see for example, R. C. Downing, FLUOROCARBON REFRIGERANTS HANDBOOK, Chapter 3, Prentice-Hall, 1988 which is incorporated herein by reference in its entirety).

“Thermal Efficiency” is a measure of how efficiently one can convert energy from a heat source to work. This property is generally used to characterize the performance of an Organic Rankine Cycle System much like COP is used to measure the efficiency of a vapor compression system. One means for estimating COP of a refrigerant at specific operating conditions is from the thermodynamic properties of the refrigerant using standard refrigeration cycle analysis techniques (see for example, Engineering and Chemical Thermodynamics, Milo D. Koretsky. Wiley 2004, page 138.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of a thermal management system of the present invention.

FIG. 2A is a schematic representation of an immersion cooling system according to the present invention.

FIG. 2B is a schematic representation of another immersion cooling system according to the present invention.

FIG. 3 is a chart of the data reported in Example 9.

FIG. 4 is a schematic illustration of a battery thermal management system according to one embodiment of the present invention.

FIG. 5 is a schematic diagram of an exemplary organic Rankine cycle.

FIG. 6 is a schematic diagram of an exemplary heat pump.

FIG. 7 is a schematic diagram of an exemplary secondary loop system.

FIG. 8 is an exemplary immersion cooling system according to Example 10.

DETAILED DESCRIPTION

The heat transfer fluid may be a refrigerant or a thermal management fluid.

The compound 1-trifluoromethyl-1,2,2-trifluorocyclobutane (“TFMCB”) has the following chemical structure:

1-trifluoromethyl-1,2,2-trifluorocyclobutane (“TFMCB”) may also be referred to by alternative names, including 1,2,2-trifluoro-1-trifluoromethyl cyclobutane, 1,2,2-trifluoro-1-trifluoromethylcyclobutane, 1,1,2-trifluoro-2-trifluoromethyl-cyclobutane, or hexafluoropropylene/ethylene cyclic dimer.

TFMCB may be manufactured by any appropriate method. Suitable methods include those set out in U.S. Pat. No. 9,856,193 and U.S. Ser. No. 10/005,705, the entire of which are hereby incorporated by reference.

Heat Transfer Fluid

The present invention provides various methods, processes and uses using a heat transfer fluid comprising TFMCB.

When the heat transfer fluid is used in thermal management (e.g. in electronic cooling), it is referred to as a thermal management fluid. When the heat transfer fluid is used in a heat transfer system (e.g. a vapour compression heat transfer system), it is referred to as a refrigerant. When the heat transfer fluid is used in an Organic Rankine Cycle, it is referred to as a working fluid.

The heat transfer fluid may comprise TFMCB in an amount of at least about 50% by weight, or at least about 70% by weight, or at least about 90% by weight or at least about 95% by weight or at least about 99% by weight, excluding non-heat transfer components, or the heat transfer fluid may consist essentially of or consist of TFMCB.

When the heat transfer fluid is used as a working fluid in an Organic Rankine Cycle, the working fluid preferably comprises at least about 50% by weight of TFMCB, based on the weight of the heat transfer components. Preferably, the working fluid comprises at least about 70% by weight of TFMCB, more preferably at least about 80% by weight of TFMCB, more preferably at least about 90% by weight of TFMCB, based on the weight of the heat transfer components.

In a particularly preferred feature of the invention, when the heat transfer fluid is used a working fluid in an Organic Rankine Cycle, the working fluid consists essentially of TFMCB. More preferably, when the heat transfer fluid is used a working fluid in an Organic Rankine Cycle, the working fluid consists of TFMCB.

Alternatively, when the heat transfer fluid is used as a working fluid in an Organic Rankine Cycle the working fluid preferably comprises TFMCB with the proviso that the working fluid is not an azeotrope which is an admixture of about 21 to 27 weight percent TFMCB, 64 to 72 weight percent trans-1,2-dichloroethylene and about 5 to 11 weight percent methanol and the working fluid is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol.

More preferably, when the heat transfer fluid is used a working fluid in an Organic Rankine Cycle, the working fluid preferably comprises at least about 50% by weight of TFMCB, based on the weight of the heat transfer components, and with the proviso that the working fluid is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol.

Preferably, the working fluid preferably comprises at least about 70% by weight of TFMCB, based on the weight of the heat transfer components, with the proviso that the working fluid is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol. More preferably the working fluid comprises at least about 80% by weight of TFMCB with the proviso that the working fluid is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol.

When the heat transfer fluid is used as a refrigerant in a high temperature heat pump, the refrigerant preferably comprises TFMCB, with the proviso that the refrigerant is not an azeotrope which is an admixture of about 21 to 27 weight percent TFMCB, 64 to 72 weight percent trans-1,2-dichloroethylene and about 5 to 11 weight percent methanol and the refrigerant is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol.

Preferably, the refrigerant comprises at least about 50% by weight of TFMCB, preferably at least about 70% by weight of TFMCB, more preferably at least about 80% by weight of TFMCB, more preferably at least about 90% by weight of TFMCB, based on the weight of the refrigerant components, excluding non-refrigerant components such as lubricants.

In a particularly preferred feature of the invention, when the heat transfer fluid comprises a refrigerant used in a high temperature heat pump, the refrigerant consists essentially of TFMCB. More preferably, when the heat transfer fluid is used a refrigerant in a high temperature heat pump, the refrigerant consists of TFMCB.

More preferably, when the heat transfer fluid is used as a refrigerant in a high temperature heat pump, the refrigerant preferably comprises at least about 50% by weight of TFMCB, based on the weight of the refrigerant components, and with the proviso that the refrigerant is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol.

Preferably, the refrigerant preferably comprises at least about 70% by weight of TFMCB, based on the weight of the refrigerant components, with the proviso that the refrigerant is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol. More preferably the refrigerant preferably comprises at least about 80% by weight of TFMCB with the proviso that the refrigerant is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol.

The heat transfer fluid may comprise one or more co-fluids. For example, the heat transfer fluid may comprise TFMCB, and one or more co-fluids selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, trans-HFO-1336mzz, HF-1234yf, HFO-1234ze(E), HFO-1233zd(E) and HFO-1233zd(Z).

When the heat transfer fluid is used as a thermal management fluid, the co-fluid is preferably HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, methanol, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, HFO-1233zd(E), HFO-1233zd(Z).

When the heat transfer fluid is used as a refrigerant, the co-fluid is preferably n-pentane, cyclopentane, cis-HFO-1336mzz, trans-HFO-1336mzz, HFO-1233zd(E), HFO-1233zd(Z) HFO-1234yf, HFO-1234ze(E).

When the heat transfer fluid comprises TFMCB and a co-fluid, the heat transfer fluid may comprise TFMCB in an amount of at least about 5% by weight, or at least about 15% by weight, or at least about 50% by weight, or at least about 70% by weight, or at least about 90% by weight, or at least 95% by weight or at least 99% by weight. The one or more co-fluids may be present in an amount of at least about 5% by weight, or at least about 10% by weight of the heat transfer fluid.

The heat transfer fluid may consist essentially of TFMCB and the one or more co-fluids. The heat transfer fluid may consist of TFMCB and the one or more co-fluids.

It will be appreciated that the heat transfer fluid may consist essentially of TFMCB. It will also be appreciated that the heat transfer fluid may consist of TFMCB.

It has surprisingly been discovered that TFMCB is non-flammable (and has no flash point) and has a GWP of about 44. This is particularly surprising, because GWP and flammability are generally inversely correlated.

The present invention thus includes heat transfer fluids that are preferably non-flammable.

When the heat transfer fluid is a refrigerant, it will be appreciated that the refrigerant is preferably a Class 1 refrigerant.

When the heat transfer fluid is a thermal management fluid, it will be appreciated that the thermal management fluid preferably has no flash point, or a flash point of above about 100 of (37.8° C.).

It has also been surprisingly discovered that TFMCB displays low levels of toxicity.

Therefore, the heat transfer fluid is preferably a low or no toxicity heat transfer fluid.

When the heat transfer fluid is a refrigerant, it will be appreciated that the refrigerant is preferably a class A refrigerant.

It is also preferred that the heat transfer fluid is non-flammable and is a low or no-toxicity heat transfer fluid.

When the heat transfer fluid is a refrigerant, it will be appreciated that the refrigerant is preferably a class A1 refrigerant and is a low or no-toxicity refrigerant.

Preferably, the heat transfer fluid (and therefore also the thermal management fluid, working fluid or refrigerant) has a low GWP. For example, the heat transfer fluid may have a GWP of not greater than about 1000, or not greater than about 700, or not greater than about 500, or not greater than about 300, or not greater than about 150. Preferably, the heat transfer fluid (and therefore also the thermal management fluid or refrigerant) has a GWP of not greater than about 150.

It will be appreciated that the heat transfer fluid (and therefore also the thermal management fluid, working fluid or refrigerant) may have a combination of one or more of the above properties.

Heat Transfer Composition

The present invention also provides a heat transfer composition comprising a heat transfer fluid of the invention.

The heat transfer composition may comprise at least about 50% by weight, or at least about 70% by weight, or at least about 90% by weight of the heat transfer fluid.

The heat transfer composition may include other components for the purpose of enhancing or providing certain functionality to the composition.

Preferably, the heat transfer composition comprises a lubricant. The lubricant lubricates the refrigeration compressor using the refrigerant. The lubricant may be present in the heat transfer composition in amounts of from about 5% to about 30% by weight of heat transfer composition. Lubricants such as Polyol Esters (POEs), Poly Alkylene Glycols (PAGs), PAG oils, polyvinyl ethers (PVEs), and poly(alpha-olefin) (PAO) and combinations thereof may be used in the heat transfer compositions of the present invention.

Preferred lubricants include POEs and PVEs, more preferably POEs. Of course, different mixtures of different types of lubricants may be used. For example, the lubricant may be a PAG if the refrigerant is used in mobile air conditioning applications.

The heat transfer composition therefore comprises a refrigerant of the invention and a lubricant selected from a POE, a PAG or a PVE.

The heat transfer composition of the present invention may consist essentially of or consist of a heat transfer fluid and lubricant as described above.

Commercially available mineral oils include Witco LP 250 (registered trademark) from Witco, Zerol 300 (registered trademark) from Shrieve Chemical, Sunisco 3GS from Wtco, and Calumet R015 from Calumet. Commercially available alkyl benzene lubricants include Zerol 150 (registered trademark). Commercially available esters include neopentyl glycol dipelargonate, which is available as Emery 2917 (registered trademark) and Hatcol 2370 (registered trademark). Other useful esters include phosphate esters, dibasic acid esters, and fluoroesters.

The heat transfer composition may include a compatibilizer for the purpose of aiding compatibility and/or solubility of the lubricant. Suitable compatibilizers may include propane, butanes, pentanes, and/or hexanes. When present, the compatibilizer is preferably present in an amount of from about 0.5% to about 5% by weight of the heat transfer composition. Combinations of surfactants and solubilizing agents may also be added to the present compositions to aid oil solubility, as disclosed by U.S. Pat. No. 6,516,837, the disclosure of which is incorporated by reference.

Uses, Methods and Systems

The present invention includes method for transferring heat as described herein, included methods as specifically described above and hereinafter.

The present invention also includes devices and systems for transferring heat as described herein, included devices and systems as specifically described above and hereinafter.

The heat transfer fluid, thermal management fluid, refrigerant, working fluid and heat transfer compositions of the invention are provided for use for heating and/or cooling as set out below.

Thus, the present invention describes a method of heating or cooling a fluid or body using a heat transfer fluid, thermal management fluid, refrigerant, working fluid or heat transfer compositions of the invention.

Thermal Management Methods, Devices, Systems and Uses.

In nearly every modern application of electronics, the dissipation of heat is an important consideration. For example, in portable and hand-held devices, the desire to miniaturize while adding functionality increases the thermal power density, which increases the challenge of cooling the electronics within them. As computational power increases within desktop computers, datacenters and telecommunications centers, so does the heat output. Power electronic devices such as the traction inverters in plug-in electric or hybrid vehicles, wind turbines, train engines, generators and various industrial processes make use of transistors that operate at ever higher currents and heat fluxes.

As discussed above, when the heat transfer fluid as described above is used in a method or device or system of cooling and/or heating in an electronic device, it is sometimes referred to herein as a thermal management fluid. The thermal management fluid therefore corresponds to the heat transfer fluid as discussed in this application. All preferred features of the heat transfer fluid as described apply to the thermal insulation fluid as described herein.

Preferred embodiments of the present thermal management methods will now be described in connection with FIG. 1 in which an operating electronic device is shown schematically as 10 having a source electrical energy and/or signals 20 flowing into and/or out of the device 10 and which generates heat as a result of its operation based on the electrical energy and/or signals 20. The thermal management fluid of the present invention is provided in thermal contact with the operating device 20 such that it removes heat, represented by the out flowing arrow 30. Heat is removed from the operating electronic device by sensible heat being added to the liquid thermal management fluid of the present invention (i.e., increasing the temperature of the liquid), or by causing a phase change in the thermal management liquid (i.e., vaporizing the liquid) or a combination of these. In preferred embodiments, the methods provide a supply of heat transfer fluid to the device 10 such that the flow of heat from the device 10 through the present heat transfer fluid 30 maintains the operating electrical device at or within a preferred operating temperature range. In preferred embodiments, the preferred operating temperature range of the electrical device is from about 70 C to about 150 C, and even more preferably from about 70 C to about 120 C, and the flow of heat 30 from the device 10 through the present heat transfer fluid energy maintains the operating electrical device at or within such preferred temperature ranges. Preferably, the heat transfer fluid 30 of the present invention, which has absorbed the heat from the device, is in thermal contact with a heat sink, represented schematically as 40, at a temperature below the temperature of the heat transfer fluid 30 and thereby transfers the heat generated by the device 10 to the heat sink 40. In this way, the heat-depleted heat transfer fluid of the present invention 50 can be returned to the electronic device 10 to repeat the cycle of cooling.

In a preferred embodiment of the present methods, the step of removing heat through the present heat transfer composition comprises evaporating the heat transfer fluid of the present invention using the heat generated by the operation of the electronic device, and the step of transferring that heat from the heat transfer composition to the heat sink comprises condensing the heat transfer fluid by rejecting heat to the heat sink. In such methods, the temperature of the heat transfer fluid during said evaporation step is greater than 50° C., or preferably greater than about 55° C., or preferably in the range of from about 55° C. to about 85° C., or preferably from about 65° C. to about 75° C. Applicants have found that the present heat transfer fluids provide excellent performance in such methods and at the same time allow the use for relatively low cost, lightweight and reliable equipment to provide the necessary cooling, as will be explained further in connection with particular embodiments as described in connection with FIG. 2A below.

In a further preferred embodiment of the present methods, the step of removing heat through the present heat transfer composition comprises adding sensible heat to the liquid heat transfer composition of the present invention (e.g., raising the temperature of the liquid up to about 70° C. or less at about atmospheric pressure, i.e., wherein the fluid is not required to be in a high pressure container or vessel) using the heat generated by the operation of the electronic device, and the step of transferring that heat from the heat transfer composition to a heat sink and thereby reducing the liquid temperature by rejecting heat to the heat sink. The cooled liquid is then returned to thermal contact with the electrical device wherein the cycle starts over. In preferred embodiments, the temperature of the heat transfer liquid that has its heat transferred to the heat sink is greater than 50° C., or preferably greater than about 55° C., or preferably in the range of from about 45° C. to about 70° C., or preferably from about 45° C. to about 65° C., and preferably is at a pressure that is about atmospheric. Applicants have found that the present heat transfer liquids provide excellent performance in such methods and at the same time allow the use for relatively low cost, lightweight and reliable equipment to provide the necessary cooling, as will be explained further in connection with particular embodiments as described in connection with FIG. 2B below.

It will be appreciated by those skilled in the art that the present invention comprises systems and methods which use both sensible heat transfer and phase change heat transfer as describe above.

A particular method according to the present invention will now be described in connection with FIGS. 2A and 2B in which an electronic device 10 is contained in an appropriate container 12, and preferably a sealed container, and is in direct contact with, and preferably fully immersed in liquid heat transfer composition of the present invention 11A (shown schematically by gray shading). The operating electronic device 10 has a source of electrical energy and/or signals 20 flowing into and/or out of the container 12 and into and/or out of device 10, which generates heat as a result of its operation based on the electrical energy and/or signals 20. As those skilled in the art will appreciated, it is a significant challenge to discover a heat transfer fluid that can perform effectively in such applications since the fluid must not only provide all of the other properties mentioned above, it must be able to do so while in intimate contact with an operating electronic device, that is, one which involves the flow of electrical current/signals. It will be appreciated that many fluids that might be otherwise viable for use in such applications will not be useable because they will either short-out the device, degrade when exposed to the conditions created by the operation of the electronic device or have some other property detrimental to operation when in contact with an operating electronic device.

In contrast, the present methods produce excellent results by providing the thermal management fluid of the present invention in direct thermal and physical contact with the device 10 as it is operating. This heat of operation is safely and effectively transferred to the thermal management fluid 11A by: (a) causing the liquid phase of the fluid to evaporate and form vapor 11B; or (b) raising the temperature of the liquid thermal management fluid 11A; or (c) a combination of (a) and (b).

In the case of the phase change heat transfer systems of the present invention, reference is made herein to FIG. 2A. In such an operation, heat is carried away from the device 10 as the liquid evaporates and the vapor rises through the remaining thermal management liquid in the container 12. The thermal management fluid vapor 11B then rejects the heat it has absorbed to a heat sink 40, which can be an enclosed heat sink 40A and/or an external heat sink 40B. An example of a heat sink that is internal to the container 12 are condenser coils 30A and 30B with circulating liquid, such as water, at a temperature below the condensing temperature of the thermal management fluid vapor. An example of a heat sink that is external to the container 12 would be passing relatively cool ambient air over the container 12 (which preferably in such case include cooling fins or the like), which will serve to condense the heat transfer vapor 11B on the interior surface of the container. As a result of this condensation, liquid thermal management fluid is returned to the pool of liquid fluid 11A in which the device 10 remains immersed in operation.

In the case of a sensible heat transfer systems of the present invention, reference is made herein to FIG. 2B. In such an operation heat is carried away from the device as the temperature of liquid increases upon accepting heat being generated by the device, which is immersed, and preferably substantially fully immersed in the thermal management fluid 11A of the present invention. The higher temperature thermal management fluid liquid 11A then rejects the heat it has absorbed to a heat sink 40, which can be an enclosed heat sink 40A and/or an external heat sink 40B. An example of a heat sink that is internal to the container 12 are cooling coils 30A and 30B with circulating liquid, such as water, at a temperature below the temperature of heated liquid. An example of a heat sink that is external to the container 12 would be removing heated liquid 11A from the container through a conduit 45 where it is thermally contacted with a cool fluid, such as might be provided by relatively cool ambient air or a refrigerant, which will serve to lower the temperature of the liquid. Cooled liquid is then returned via conduit 46.

Optionally, but preferably in certain embodiments involving thermal management of the batteries used in electronic vehicles, the thermal management system includes a heating element which is able to heat the thermal management fluid, such as for example an electrical heating element 60 which is also immersed in the thermal management fluid. As those skilled in the art will appreciate, the batteries in electronic vehicles (which would correspond to the operating electronic device 10 in FIGS. 2A and 2B) can reach relatively low temperatures while parked outside in the winter months in many geographical locations, and frequently such low temperature conditions are not desirable for battery operation. Accordingly, the thermal management system of the present invention can include sensors and control modules (not shown) which turn on the heating element when the battery temperature is below a predetermined level. In such a case, the heater 60 would be activated, the thermal management liquid 11A would be heated, and would in turn transfer this heat to the electronic device 10 until the minimum temperature is reached. Thereafter during operation, the thermal management fluid of the present invention would serve the cooling function as described above.

For the purposes of this invention, the thermal management fluid can be in direct contact with the heat-generating component or in indirect contact with the heat-generating component.

When the thermal management fluid is in indirect contact with the heat-generating component, the thermal management fluid can be used in a closed system in the electronic device, which may include at least two heat exchangers. When the thermal management fluid is used to cool the heat-generating component, heat can be transferred from the component to the thermal management fluid, usually through a heat exchanger in contact with at least a part of the component or the heat can be transferred to circulating air which can conduct the heat to a heat exchanger that is in thermal contact with the thermal management fluid.

In a particularly preferred feature of the present invention, the thermal management fluid is in direct contact with the heat-generating component. In particular, the heat generating component is fully or partially immersed in the thermal management fluid. Preferably the heat generating component is fully immersed in the thermal management fluid. The thermal management fluid, as a warmed fluid or as a vapor, can then be circulated to a heat exchanger which takes the heat from the fluid or vapor and transfers it to the outside environment. After this heat transfer, the cooled thermal management fluid (cooled or condensed) is recycled back into the system to cool the heat-generating component.

When the thermal management fluid is a single-phase liquid, it will remain liquid when heated by the heat-generating component. Thus, the thermal management fluid can be brought into contact with the heat generating component, resulting in the removal of the heat from the heat generating component and the production of a thermal management fluid with a higher temperature. The thermal management fluid is then transported to a secondary cooling loop, such as a radiator or another refrigerated system. An example of such a system is illustrated in FIG. 2, where the thermal management fluid enters a battery pack enclosure containing a number of cells and exits the enclosure having taken up heat from the battery pack.

When the thermal management fluid has two phases, the heat-generating component is in thermal contact with the thermal management fluid and transfers heat to the thermal management fluid, resulting in the boiling of the thermal management fluid. The thermal management fluid is then condensed. An example of such a system is where the heat-generating component is immersed in the thermal management fluid and an external cooling circuit condenses the boiling fluid into a liquid state.

Electrical conductivity of a thermal management fluid becomes important if the fluid comes in direct contact with the electronic components of the electronic device (such as in direct immersion cooling), or if the thermal management fluid leaks out of a cooling loop or is spilled during maintenance and comes in contact with the electrical circuits. Thus, the thermal management fluid is preferably an electrically insulating thermal management fluid.

The thermal management fluid may be recirculated passively or actively in the device, for example by using mechanical equipment such as a pump. In a preferred feature of the present invention, the thermal management fluid is recirculated passively in the device.

Passive recirculating systems work by transferring heat from the heat-generating component to the thermal management fluid until it typically is vaporized, allowing the heated vapor to proceed to a heat exchange surface at which it transfers its heat to the heat exchanger surface and condenses back into a liquid. It will be appreciated that the heat exchange surface can be part of a separate heat exchange unit and/or can be integral with the container, as described above for example in connection with FIG. 2. The condensed liquid then returns, preferably fully passively by the force of gravity, into the thermal management fluid in contact with the heat-generating component. Thus, in a preferred feature of the invention, the step of transferring heat from the heat-generating component to the thermal management fluid causes the thermal management fluid to vaporize.

Examples of passive recirculating systems include a heat pipe or a thermosyphon. Such systems passively recirculate the thermal management fluid using gravity. In such a system, the thermal management fluid is heated by the heat-generating component, resulting in a heated thermal management fluid which is less dense and more buoyant. This thermal management fluid travels to a storage container, such as a tank where it cools and condenses. The cooled thermal management fluid then flows back to the heat source.

The electronic device includes a heat-generating component. The heat-generating component can be any component that includes an electronic element that as part of its operation generates heat. For the purposes of this invention, the heat generating component can be selected from semiconductor integrated circuits (ICs), electrochemical cells, power transistors, resistors, and electroluminescent elements, such as microprocessors, wafers used to manufacture semiconductor devices, power control semiconductors, electrical distribution switch gear, power transformers, circuit boards, multi-chip modules, packaged or unpackaged semiconductor devices, semiconductor integrated circuits, fuel cells, lasers (conventional or laser diodes), light emitting diodes (LEDs), and electrochemical cells, e.g. used for high power applications such as, for example, hybrid or electric vehicles.

For the purpose of this invention, the electronic device can be selected from personal computers, microprocessors, servers, cell phones, tablets, digital home appliances (e.g. televisions, media players, games consoles etc.), personal digital assistants, Datacenters, batteries both stationary and in vehicles, hybrid or electric vehicles, wind turbine, train engine, or generator. Preferably the electronic device is a hybrid or electric vehicle.

The present invention further relates to an electronic device comprising a thermal management fluid of the invention. For the purposes of this invention, the thermal management fluid is provided for cooling and/or heating the electronic device.

The present invention further relates to an electronic device comprising a heat generating component and a thermal management fluid of the invention. For the purposes of this invention, the electronic device can further comprise a heat exchanger, particularly where the heat exchanger is in contact with at least a part of the heat generating component.

The present invention further relates to an electronic device comprising a heat generating component, a heat exchanger, a pump and a thermal management fluid of the invention.

For the purposes of this invention, the heat generating component can be selected from semiconductor integrated circuits (ICs), electrochemical cells, power transistors, resistors, and electroluminescent elements, such as microprocessors, wafers used to manufacture semiconductor devices, power control semiconductors, electrical distribution switch gear, power transformers, circuit boards, multi-chip modules, packaged or unpackaged semiconductor devices, semiconductor integrated circuits, fuel cells, lasers (conventional or laser diodes), light emitting diodes (LEDs), and electrochemical cells, e.g. used for high power applications such as, for example, hybrid or electric vehicles.

For the purpose of this invention, the electronic device can be selected from personal computers, microprocessors, servers, cell phones, tablets, digital home appliances (e.g. televisions, media players, games consoles etc.), personal digital assistants, Datacenters, hybrid or electric vehicles, batteries both stationary and in vehicles, wind turbine, train engine, or generator, preferably wherein the electronic device is a hybrid or electric vehicle.

The invention further relates to the use of a thermal management fluid of the invention for cooling an electronic device. For the purpose of this invention, the electronic device can be selected from personal computers, microprocessors, servers, cell phones, tablets, digital home appliances (e.g. televisions, media players, games consoles etc.), personal digital assistants, Datacenters, hybrid or electric vehicles, batteries both stationary and in vehicles, wind turbine, train engine, or generator, preferably wherein the electronic device is a hybrid or electric vehicle.

Uses of Refrigerant and Heat Transfer Composition

The invention also provides a heat transfer system comprising a refrigerant or a heat transfer composition of the invention. It will be appreciated that the heat transfer systems described herein may be vapor compression systems having an evaporator, a condenser and a compressor in fluid communication.

The refrigerant or heat transfer composition of the invention may be used as a secondary fluid.

It will be appreciated that the refrigerant or heat transfer composition of the invention may be used in a variety of different heat transfer applications.

Organic Rankine Cycle

As discussed above, when the heat transfer fluid as described above is used in an Organic Rankine cycle, it is referred to as a working fluid. The working fluid therefore corresponds to the heat transfer fluid as discussed in this application. All preferred features of the heat transfer fluid apply to the working fluid as described herein.

Rankine cycle systems are known to be a simple and reliable means to convert heat energy into mechanical shaft power. In industrial settings, it may be possible to use flammable working fluids such as toluene and pentane, particularly when the industrial setting has large quantities of flammables already on site in processes or storage. However, for instances where the risk associated with use of a flammable and/or toxic working fluid is not acceptable, such as power generation in populous areas or near buildings, it is necessary to use non-flammable and/or non-toxic refrigerants as the working fluid. There is also a drive in the industry for these materials to be environmentally acceptable in terms of GWP.

The process for recovering waste heat in an Organic Rankine cycle involves pumping liquid-phase working fluid through a boiler where an external (waste) heat source, such as a process stream, heats the working fluid causing it to evaporate into a saturated or superheated vapor. This vapor is expanded through a turbine wherein the waste heat energy is converted into mechanical energy. Subsequently, the vapor phase working fluid is condensed to a liquid and pumped back to the boiler in order to repeat the heat extraction cycle.

Referring to FIG. 6, in an exemplary organic Rankine cycle system 70, working fluid is circulated between an evaporator device 71 and a condenser 75, with a pump device 72 and an expansion device 74 functionally disposed therebetween. In the illustrated embodiment, an external flow of fluid is directed to evaporator 71 via external warm conduit 76. External warm conduit 76 may carry fluid from a warm heat source, such as a waste heat source from industrial processes (e.g., power generation), flue gases, exhaust gases, geothermal sources, etc.

Evaporator 71 is configured as a heat exchanger which may include, e.g., a series of thermally connected, but fluidly isolated, tubes carrying fluid from warm conduit 76 and fluid from working fluid conduit 77B respectively. Thus, evaporator 71 facilitates the transfer of heat Q_(IN) from the warm fluid arriving from external warm conduit 76 to the relatively cooler (e.g., “cold”) working fluid arriving from expansion device 74 via working fluid conduit 77B.

The working fluid issued from evaporator 71, having thus been warmed by the absorption of heat Q_(IN), then travels through working fluid conduit 78A to pump 72. Pump 72 pressurizes the working fluid, thereby further warming the fluid through external energy inputs (e.g., electricity). The resulting “hot” fluid passes to an input of condenser 75 via conduit 78B, optionally via a regenerator 73 as described below.

Condenser 75 is configured as a heat exchanger similar to evaporator 71, and may include, e.g., a series of thermally connected, but fluidly isolated, tubes carrying fluid from cool conduit 79 and fluid from working fluid conduit 78B respectively. Condenser 75 facilitates the transfer of heat Q_(OUT) to the cool fluid arriving from external cool conduit 79 to the relatively warmer (e.g., “hot”) working fluid arriving from pump 72 via working fluid conduit 78B.

The working fluid issued from condenser 75, having thus been cooled by the loss of heat Q_(OUT), then travels through working fluid conduit 77A to expansion device 74. Expansion device 74 allows the working fluid to expand, thereby further cooling the fluid. At this stage, the fluid may perform work, e.g., by driving a turbine. The resulting “cold” fluid passes to an input of evaporator 71 via conduit 77B, optionally via a regenerator 73 as described below, and the cycle begins anew.

Thus, working fluid conduits 77A, 77B, 78A and 78B define a closed loop such that the working fluid contained therein may be reused indefinitely, or until routing maintenance is required.

In the illustrated embodiment, regenerator 73 may be functionally disposed between evaporator 71 and condenser 75. Regenerator 73 allows the “hot” working fluid issued from pump 72 and the “cold” working fluid issued from expansion device 74 to exchange some heat, potentially with a time lag between deposit of heat from the hot working fluid and release of that heat to the cold working fluid. In some applications, this can increase the overall thermal efficiency of Rankine cycle system 70

Therefore, the invention relates to an organic Rankine cycle comprising a working fluid of the present invention.

The invention further relates to the use of a working fluid of the invention in an Organic Rankine Cycle.

The invention also provides a process for converting thermal energy to mechanical energy in a Rankine cycle, the method comprising the steps of i) vaporizing a working fluid of the invention with a heat source and expanding the resulting vapor, then ii) cooling the working fluid with a heat sink to condense the vapor, wherein the working fluid is a refrigerant or heat transfer composition of the invention.

The mechanical work may be transmitted to an electrical device such as a generator to produce electrical power.

The heat source may be provided by a thermal energy source selected from industrial waste heat, solar energy, geothermal hot water, low pressure steam, distributed power generation equipment utilizing fuel cells, prime movers, or an internal combustion engine. The low pressure steam is a low pressure geothermal steam or is provided by a fossil fuel powered electrical generating power plant.

The heat source is preferably provided by a thermal energy source selected from industrial waste heat, or an internal combustion engine.

It will be appreciated that the heat source temperatures can vary widely, for example from about 90° C. to >800° C., and can be dependent upon a myriad of factors including geography, time of year, etc. for certain combustion gases and some fuel cells.

Systems based on sources such as waste water or low pressure steam from, e.g., a plastics manufacturing plants and/or from chemical or other industrial plant, petroleum refinery, and related word forms, as well as geothermal sources, may have source temperatures that are at or below about 175° C. or at or below about 100° C., and in some cases as low as about 90° C. or even as low as about 80° C. Gaseous sources of heat such as exhaust gas from combustion process or from any heat source where subsequent treatments to remove particulates and/or corrosive species result in low temperatures may also have source temperatures that are at or below 200° C., at or below about 175° C., at or below about 130° C., at or below about 120° C., at or below about 100° C., at or below about 100° C., and in some cases as low as about 90° C. or even as low as about 80° C.

However, it is preferred that the heat source has a temperature of at least about 200° C., for example of from about 200° C. to about 400° C.

In an alternative preferred embodiment, the heat source has a temperature of from 400 to 800° C., more preferably 400 to 600° C.

Heat Pump

As discussed above, when the heat transfer fluid as described above is used in a heat pump, it is referred to as a refrigerant. The refrigerant therefore corresponds to the heat transfer fluid as discussed this application. All preferred features of the heat transfer fluid as described apply to the refrigerant as described herein.

The refrigerant or heat transfer composition of the invention may be used in a high temperature heat pump system.

Referring to FIG. 6, in one exemplary heat pump system, compressor 80, such as a rotary, piston, screw, or scroll compressor, compresses the refrigerant, which is conveyed to a condenser 82 to release heat Q_(OUT) to a first location, followed by passing the refrigerant through an expansion device 84 to lower the refrigerant pressure, followed by passing the refrigerant through an evaporator 86 to absorb heat Q_(IN) from a second location. The refrigerant is then conveyed back to the compressor 80 for compression.

The present invention provides a method of heating a fluid or body using a high temperature heat pump, said method comprising the steps of (a) condensing a refrigerant composition of the invention in the vicinity of the fluid of body or be heated, and (b) evaporating said refrigerant.

Examples of high temperature heat pumps include a heat pump tumble dryer or an industrial heat pump. It will be appreciated the heat pump may comprise a suction line/liquid line heat exchanger (SL-LL HX). By “high temperature heat pump”, it is meant a heat pump that is able to generate temperatures of at least about 80° C., preferably at least about 90° C., preferably at least about 100° C., more preferably at least about 110° C.

Secondary Loop System

As discussed above, when the heat transfer fluid as described above is used in a secondary loop system, it is referred to as a refrigerant. The refrigerant therefore corresponds to the heat transfer fluid as discussed in this application. All preferred features of the heat transfer fluid as described in section 1 apply to the refrigerant as described herein.

The refrigerant of the present invention may be used as secondary refrigerant fluid in a secondary loop system.

A secondary loop system contains a primary vapor compression system loop that uses a primary refrigerant and whose evaporator cools the secondary loop fluid. The secondary refrigerant fluid then provides the necessary cooling for an application. The secondary refrigerant fluid must be non-flammable and have low-toxicity since the fluid in such a loop is potentially exposed to humans in the vicinity of the cooled space. In other words, the refrigerant or heat transfer composition of the present invention may be used as a “secondary refrigerant fluid” in a secondary loop system.

Referring to FIG. 7, one exemplary secondary loop system includes a primary loop 90 and a secondary loop 92. In primary loop 90, compressor 94, such as a rotary, piston, screw, or scroll compressor, compresses a primary refrigerant, which is conveyed to a condenser 96 to release heat Q_(OUT) to a first location, followed by passing the primary refrigerant through an expansion device 98 to lower the refrigerant pressure, followed by passing the primary refrigerant through a refrigerant/secondary fluid heat exchanger 100 to exchange heat Q_(IN) with a secondary fluid, with the secondary fluid pumped through secondary loop 92 via a pump 102 to a secondary loop heat exchanger 104 to exchange heat with a further location, for example to absorb heat Q_(IN-S) to providing cooling to the further location.

The primary fluid used in the primary loop (vapor compression cycle, external/outdoors part of the loop) may be selected from but not limited to HFO-1234ze(E), HFO-1234yf, propane, R455A, R32, R466A, R44B, R290, R717, R452B, R448A, and R449A, preferably HFO-1234ze(E), HFO-1234yf, or propane.

The secondary loop system may be used in refrigeration or air conditioning applications, that is,

the secondary loop system may be a secondary loop refrigeration system or a secondary loop air conditioning system.

Examples of refrigeration systems which can include a secondary loop refrigeration system include:

-   -   a low temperature refrigeration system,     -   a medium temperature refrigeration system,     -   a commercial refrigerator,     -   a commercial freezer,     -   an industrial freezer,     -   an industrial refrigerator and     -   a chiller.

Examples of air conditioning systems which can include a secondary loop air conditioning system include in mobile air conditioning systems or stationary air conditioning systems. Mobile air-conditioning systems including air conditioning of road vehicles such as automobiles, trucks and buses, as well as air conditioning of boats, and trains. For example, where a vehicle contains a battery or electric power source.

Examples of stationary air conditioning systems include:

-   -   a chiller, particularly a positive displacement chiller, more         particularly an air cooled or water-cooled direct expansion         chiller, which is either modular or conventionally singularly         packaged,     -   a residential air conditioning system, particularly a ducted         split or a ductless split air conditioning system,     -   a residential heat pump,     -   a residential air to water heat pump/hydronic system,     -   an industrial air conditioning system     -   a commercial air conditioning system, particularly a packaged         rooftop unit and a variable refrigerant flow (VRF) system;     -   a commercial air source, water source or ground source heat pump         system.

A particularly preferred heat transfer system according to the present invention is an automotive air conditioning system comprising a vapour compression system (the primary loop) and a secondary loop air conditioning system, wherein the primary loop contains HFO-1234yf as the refrigerant and the second loop contains a refrigerant or heat transfer composition of the invention. In particular, the secondary loop can be used to cool a component in the car engine, such as the battery.

It will be appreciated the secondary loop air conditioning or refrigeration system may comprise a suction line/liquid line heat exchanger (SL-LL HX).

Methods

The heat transfer fluids, or heat transfer compositions of the invention may be used as a replacement for existing fluids.

The invention provides a method of replacing an existing heat transfer fluid in a heat transfer system, said method comprising the steps of (a) removing at least a portion of said existing heat transfer fluid from said system, and subsequently (b) introducing into said system a heat transfer fluid of the invention.

Step (a) may involve removing at least about 5 wt. %, at least about 10 wt. %, at least about 15 wt. %, at least about 50 wt. % at least about 70 wt. %, at least about 90 wt. %, at least about 95 wt. %, at least about 99 wt. % or at least about 99.5 wt. % or substantially all of said existing heat transfer fluid from said system prior to step (b).

The method may optionally comprise the step of flushing said system with a solvent after conducting step (a) and prior to conducting step (b).

For the purposes of this invention, the heat transfer fluid can be used to replace an existing fluid in an electronic device, in an Organic Rankine cycle, in a high temperature heat pump or in a secondary loop.

For example, the thermal management fluid of the invention may be used as a replacement for existing fluids such as HFC-4310mee, HFE-7100 and HFE-7200. Alternatively, the thermal management fluid can be used to replace water and glycol. The replacement may be in existing systems, or in new systems which are designed to work with an existing fluid. Alternatively, the thermal management fluid can be used in applications in which the existing refrigerant was previously used.

For example, the refrigerants of the invention may be used as a replacement for existing refrigerants such as HFC-245fa, HFC-134a, HFC-404A and HFC-410A. The refrigerant may be used in applications in which the existing refrigerant was previously used. Alternatively, the refrigerant may be used to retrofit an existing refrigerant in an existing system. Alternatively, the refrigerant may be used in new systems which are designed to work with an existing refrigerant.

The invention provides a method of replacing an existing refrigerant in a heat transfer system, said method comprising the steps of (a) removing at least a portion of said existing refrigerant from said system, and subsequently (b) introducing into said system a refrigerant of the invention. The existing refrigerants may be selected from HFC-245fa, HFC-134a, HFC-404A and HFC-410A

Step (a) may involve removing at least about 5 wt. %, at least about 10 wt. %, at least about 15 wt. %, at least about 50 wt. % at least about 70 wt. %, at least about 90 wt. %, at least about 95 wt. %, at least about 99 wt. % or at least about 99.5 wt. % of said existing refrigerant from said system prior to step (b).

The method may optionally comprise the step of flushing said system with a solvent after conducting step (a) and prior to conducting step (b).

EXAMPLES Example 1 Organic Rankine Cycle

This example illustrates that TFMCB is useful as a working fluid in an Organic Rankine cycle based on a comparison of the estimated thermal efficiency of various working fluids in an organic Rankine cycle.

The ORC system was assumed to contain a condenser, pump, boiler and turbine. Using the properties of each working fluid at the specified conditions of each unit operation, as defined in Table 1, the thermal efficiencies were evaluated. The results are shown in Table 1 below.

TABLE 1 Process Specifications Boiler Boiler Critical Super- Isentropic Condensing Isentropic Estimated Working Temp Temp heat Efficiency Temp Efficiency Thermal Fluid (° C.) (° C.) (° C.) (Turbine) (° C.) (Pump) Efficiency Condition 1 TFMCB 144 225 1 0.8 35 0.8 15.08% R245fa 144 154 1 0.8 35 0.8 15.41% R1233zd(E) 144 166 1 0.8 35 0.8 15.92% Condition 2 TFMCB 210 225 1 0.8 35 0.8 18.18% R245fa 144 154 1 0.8 35 0.8 15.41% R1233zd(E) 156 166 1 0.8 35 0.8 16.66%

Condition 1 compares the thermal efficiency of TFMCB, HFC-245fa and HFCO-1233zd(E) at the same boiler temperature, 144° C. The tests at condition 1 demonstrate that TFMCB has a comparable thermal efficiency to HFC-245fa and HFCO-1233zd(E) at this temperature. At higher boiler temperature conditions (Condition 2) the results indicate that TFMCB is a more efficient working fluid than HFC-245fa and HFCO-1233zd(E).

Example 2 Heat Transfer and Pressure Drop of TFMCB and 3M Novec 7200 in a Heat Exchanger

Batteries of electric vehicles develop heat during operation when charging and discharging. The typical design of vehicle batteries differs between three types: Cylindrical cells, pouch cells and prismatic cells. All three types have different considerations in terms of heat transfer due to their shape. Prismatic and pouch cells are often used with cooling plates due to the straight outer faces. Cylindrical cells employ cooling ribbons that are in thermal contact with the outer shell of the cells. Extensive heat generation during charging and discharging of the cells can lead to an increase in temperature that can cause decreasing performance and reduced battery lifetime.

A battery cooling plate set up may be used to provide active cooling to a battery and remove the heat (e.g. to remove heat from the battery of an electric vehicle). In this Example, the performance of two fluids, 3M Novec 7200 and TFMCB, were analyzed for their ability to provide cooling in single phase heat transfer.

It will be appreciated that the convective heat transfer can occur either by direct contact, I.e. when the battery is immersed in the fluid that may be pumped through the battery enclosure or indirectly, i.e. by using a cooling plate with a combination of convective and conductive heat transfer.

The present example used a round tube with an internal diameter of 0.55 inches to provide a cooling load of 10246 BTU/h (3kVV). The tube length was 30 ft (9.14 m) with an assumed pressure drop of 2.9PS1 (20 kPa). The fluid temperature was 7.2 C (45 F). The internal heat transfer coefficient was determined for turbulent flow. The necessary mass flow rate to remove the cooling load was determined for both fluids. The results of the comparison are shown in Table 2. It can be seen in the results that the necessary mass flow rate to remove the generated heat is lower for TFMCB than for 3M Novec 7200. This indicates a reduced input to remove the heat from the heat exchanger set up. The useful output (I.e. the heat transfer coefficient) is 7% higher for TFMCB compared to 3M Novec 7200.

TABLE 2 Heat Transfer and Pressure Drop For Heat Exchanger Set Up Mass Flow Prandtl Internal heat Rate Number transfer coefficient lb/s [—] BTU/(h-ft²-F) TFMCB 0.94  9.6 324.7 3M Novec 7200 0.98 10.4 303.4 TFMCB relative to 96%  93% 107% 3M Novec 7200

Example 3 Thermodynamic Performance of a Secondary AC System

The efficiency of secondary loop air conditioning system, as determined by the estimated coefficient of performance (COP), was evaluated for the use of TFMCB as a secondary refrigerant with R1234ze(E), R1234yf, and propane as primary refrigerant options. The system was composed of a vapor-compression primary loop and a pumped two-phase secondary loop that were thermally connected by an internal heat exchanger. This internal heat exchanger acted as an evaporator for the primary loop and a condenser for the secondary loop. Using the thermodynamic properties of the primary and secondary refrigerants at the specified conditions of each unit operation, defined in Table 3A., the COP was evaluated relative to the performance of R410A in an air conditioning system.

TABLE 3A Operating Conditions Operating T_(cond.) T_(cond sink) □T_(SC) T_(evap.) evap sink □T_(SH) □Isentropic □Volumetric T_(IHX-SH) T_(IHX-Sat) Conditions (° C.) (° C.) (° C.) (° C.) (° C.) (° C.) (—) (—) ° C.) ° C.) Basic Cycle 45 35 −5 7 27 +5 70% 100% N/A N/A (R410A) Secondary 45 35 −5 7 27 (flooded) 70% 100% +5 +5 Cycle (“X”/TFMCB) Nomenclature: T = Temperature, □ = Efficiency, □ = Difference, SC = Sub-cooling, SH = Superheat, IHX = Intermediate Heat Exchanger, Sat = Saturation

TABLE 3B Performance of secondary AC cycle Primary Refrigerant Secondary GWP GWP (“X”) Refrigerant Primary Secondary Capacity Efficiency R410A 1924 100% 100%  R1234ze(E) TFMCB <1 44 100% 91% R1234yf TFMCB <1 44 100% 88% Propane TFMCB 3 44 100% 90%

-   -   Table 3B shows the thermodynamic performance of the secondary AC         system with different primary refrigerants and using TFMCB as         secondary refrigerant.     -   The capacity of the secondary AC system was matched to R410A         system in all the cases.

TABLE 3C Condensing temperatures required to match efficiency of R410A Primary Refrigerant Secondary GWP GWP Tcond (“X”) Refrigerant Primary Secondary (° C.) Efficiency R410A 1924 45.0 100% R1234ze(E) TFMCB <1 44 42.1 100% R1234yf TFMCB <1 44 41.0 100% Propane TFMCB 3 44 41.6 100%

-   -   In order to match the efficiency (COP), heat transfer area can         be added to the condenser which may reduce the condensing         temperature and thereby improve efficiency.     -   The size of the condenser is inversely proportional to the         condensing temperature required to match efficiency, hence         higher condensing temperature is desirable.     -   Table 3 C shows the condensing temperatures required to match         efficiency with different refrigerants.

TABLE 3D Efficiency at different ambient conditions Primary Refrigerant Secondary GWP GWP Efficiency Efficiency Efficiency (“X”) Refrigerant Primary Secondary @35° C. @45° C. @55° C. R410A 1924 100% 72% 52% R1234ze(E) TFMCB <1 44 100% 75% 57% R1234yf TFMCB <1 44 100% 73% 54% Propane TFMCB 3 44 100% 75% 57%

-   -   Table 3D shows the performance of the secondary AC system with         different refrigerants at increasing ambient temperatures         compared to 35 C ambient temperature.

All the refrigerants show less efficiency degradation compared to R410A as the ambient temperature is increased from 35° C. to 55° C.

Example 4

High temperature heat pump application using TFMCB

High temperature heat pumps can utilize waste heat and provide high heat sink temperatures. TFMCB provides efficiency benefits over R245fa over all condensing temperatures tested.

Operating conditions:

-   -   Condensing temperature varied between 90° C., 100° C. and 110°         C.     -   Subcooling:10° C.     -   Evaporating temperature: 25° C.     -   Evaporator Superheat: 15° C.     -   Isentropic efficiency: 65%

TABLE 4 Relative heating COP at varying condensing temperatures Condensing temperature Fluid 90° C. 100° C. 110° C. R245fa 100.0% 100.0% 100.0% TFMCB 101.7% 102.0% 102.6%

Example 5 Thermodynamic Performance of a Secondary Loop Medium Temperature Refrigeration System

The efficiency of secondary loop medium temperature refrigeration system, as determined by the estimated coefficient of performance (COP), was evaluated for the use of TFMCB as a secondary refrigerant with R1234ze(E), R1234yf, and propane as primary refrigerant options. The system was composed of a vapor-compression primary loop and a pumped two-phase secondary loop that were thermally connected by an internal heat exchanger. This internal heat exchanger acted as an evaporator for the primary loop and a condenser for the secondary loop. Using the thermodynamic properties of the primary and secondary refrigerants at the specified conditions of each unit operation, defined in Table 5A., the COP was evaluated relative to the performance of R134a in an air conditioning system.

Thus, a secondary medium temperature refrigeration system using the compositions of the invention is able to match the efficiency of R134a with system design changes while using an ultra low GWP, non-flammable refrigerant inside the store.

TABLE 5A Operating conditions Operating T_(cond.) T_(cond sink) □T_(SC) T_(evap.) T_(evap sink) □T_(SH) □Isentropic □Volumetric □T_(IHX-SH) □T_(IHX-Sat) Conditions (° C.) (° C.) (° C.) (° C.) (° C.) (° C.) (—) (—) (° C.) (° C.) Basic Cycle 45 35 −5 −8 27 +5 70% 100% N/A N/A (R134a) Secondary 45 35 −5 −8 27 0 70% 100% +5 +5 Cycle (flooded) (“X”/TFMCB) Nomenclature: T = Temperature, □ = Efficiency, □ = Difference, SC = Sub-cooling, SH = Superheat, IHX = Intermediate Heat Exchanger, Sat = Saturation

TABLE 5B Performance of secondary refrigeration cycle Primary Refrigerant Secondary GWP GWP (“X”) Refrigerant Primary Secondary Capacity Efficiency R134a 1300 100% 100%  R1234ze(E) TFMCB <1 44 100% 87% R1234yf TFMCB <1 44 100% 82% Propane TFMCB 3 44 100% 86%

-   -   Table 5B shows the thermodynamic performance of the secondary         refrigeration system with different primary refrigerants and         using TFMCB as secondary refrigerant.     -   The capacity of the secondary refrigeration system was matched         to R134a system in all the cases.

TABLE 5C Condensing temperatures required to match efficiency of R134a Primary Refrigerant Secondary GWP GWP Tcond (“X”) Refrigerant Primary Secondary (° C.) Efficiency R134a 1300 45.0 100% R1234ze(E) TFMCB <1 44 39.5 100% R1234yf TFMCB <1 44 38.0 100% Propane TFMCB 3 44 39.2 100%

-   -   In order to match the efficiency (COP). heat transfer area can         be added to the condenser which may reduce the condensing         temperature and thereby improve efficiency.     -   The size of the condenser is inversely proportional to the         condensing temperature required to match efficiency, hence         higher condensing temperature is desirable.     -   Table 5C shows the condensing temperatures required to match         efficiency with different refrigerants.

TABLE 5D Efficiency at different ambient conditions Primary Refrigerant Secondary GWP GWP Efficiency Efficiency Efficiency (“X”) Refrigerant Primary Secondary @35° C. @45° C. @55° C. R134a 1300 100% 78% 60% R1234ze(E) TFMCB <1 44 100% 78% 61% R1234yf TFMCB <1 44 100% 76% 57% Propane TFMCB 3 44 100% 78% 61%

-   -   Table 5D shows the performance of the secondary refrigeration         system with different refrigerants at increasing ambient         temperatures compared to 35 C ambient temperature.

All the refrigerants show similar efficiency degradation compared to R134a as the ambient temperature is increased from 35° C. to 55° C.

Example 6 Miscibility of TFMCB

The miscibility of TFMCB with various refrigeration lubricants is tested. The lubricants tested are Polyol Ester oil (Mobil EAL 22 cc and Solest 120) and polyalkylene glycol (PAG) oil (Toyota ND-oil 8). For each refrigerant/oil combination, three compositions are tested, namely 5, 20 and 50 weight percent of lubricant, with the balance of each being the compound of the present invention being tested.

The lubricant compositions are placed in heavy-walled glass tubes. The tubes are evacuated, the refrigerant compound in accordance with the present invention is added, and the tubes are then sealed. The tubes are then put into an air bath environmental chamber, the temperature of which is varied from about −50° C. to 70° C. At roughly 10° C. intervals, visual observations of the tube contents are made for the existence of one or more liquid phases. In a case where more than one liquid phase is observed, the mixture is reported to be immiscible. In a case where there is only one liquid phase observed, the mixture is reported to be miscible. In those cases where two liquid phases were observed, but with one of the liquid phases occupying only a very small volume, the mixture is reported to be partially miscible.

The polyalkylene glycol and ester oil lubricants are judged to be miscible in all tested proportions over the entire temperature range.

Example 7 Compatibility of TFMCB

The compatibility of the refrigerant compounds and compositions of the present invention with PAG lubricating oils while in contact with metals used in refrigeration and air conditioning systems is tested at 350° F., representing conditions much more severe than are found in many refrigeration and air conditioning applications.

Aluminum, copper and steel coupons are added to heavy walled glass tubes. Two grams of oil are added to the tubes. The tubes are then evacuated and one gram of refrigerant is added. The tubes are put into an oven at 350° F. for one week and visual observations are made. At the end of the exposure period, the tubes are removed.

This procedure was done for the following combinations of oil and the compound of the present invention:

a. TFMCB and Toyota ND-oil 8

b. TFMCB and Mobil EAL 22 cc

c. TFMCB and Solest 120.

In all cases, there is minimal change in the appearance of the contents of the tube. This indicates that the compounds and compositions of the present invention are stable in contact with aluminum, steel and copper found in refrigeration and air conditioning systems, and the types of lubricating oils that are likely to be included in such compositions or used with such compositions in these types of systems.

Example 8 Compatibility of TFMCB

TFMCB and elastomer samples were placed into 40 cm3 stainless steel cylinders which was heated in an 80° C. oven for a period of 14 days.

Change Material Hardness Weight Volume Nylon 6.02% 0.28% 0.10% PTFE 3.57% 2.85% 4.22% Buna-N/Nitrile/NBR −5.13% −4.37% −6.79% EPDM 0.37% −1.77% −2.58% Neoprene 20.15% −7.08% −11.86% Silicone 1.49% −1.58% −3.66% Fluoroelastomer/Viton −3.58% 6.37% 8.47%

Conclusions: Overall no change in appearance of the material samples. TFMCB shows good compatibility with plastics and elastomers.

Example 9 Sensible Heat Immersion Cooling Application Using TFMCB

Batteries of electric vehicles develop heat during operation when charging and discharging. The typical design of vehicle batteries differs between three types: Cylindrical cells, pouch cells and prismatic cells. All three types have different considerations in terms of heat transfer due to their shape. Extensive heat generation during charging and discharging of the cells can lead to an increase in temperature that can cause decreasing performance and reduced battery lifetime.

It will be appreciated that TFMCB is a dielectric and nonflammable fluid which allows for direct cooling of the battery cells that are immersed in the fluid.

The present example considers a battery module that consists of 1792 cylindrical battery cells of 18650 type. In one case the battery module is cooled by a 50/50 mixture of water/glycol in a flat tube heat exchanger that is on contact with the battery cells. In the other case the cells are immersed in TFMCB, i.e. are in direct contact with the fluid. The waste heat for the battery module is 8750 W that is evenly distributed over the total number of cells. The assumptions and operating conditions are listed in Table 6.

It can be seen in the results for minimum and maximum cell temperatures that are listed in Table 7 and for visualization in FIG. 1 that immersion cooling using TFMCB provides lower maximum cell temperatures compared to the heat exchanger using water/glycol. This has a beneficial effect on battery cell performance and lifetime.

TABLE 6 Assumptions for Battery module design and operating conditions Parameter Unit Water/Glycol TFMCB Battery diameter [mm] 18.5 18.5 Battery gap [mm] 3.8 1.5 Battery height [mm] 65 Number of batteries [—] 1792 Battery mass [g] 49 Battery specific heat [J/kgK] 830 Total battery module waste heat [W] 8750 Fluid flow rate [kg/s] 0.1 Initial module temperature [° C.] 30 Fluid inlet temperature [° C.] 10 Cooling channel height [mm] 30 n/a Cooling channel width [mm] 2.8 n/a Heat exchanger flat tube wall [mm] 0.5 n/a thickness Heat exchanger flat tube thermal [W/mK] 3 n/a conductivity Heat exchanger flat tube relative [—] 0.0003 n/a surface roughness

TABLE 7 Minimum and maximum cell temperatures in battery module Minimum cell temperature Maximum cell temperatures [° C.] [° C.] Time Water/Glycol 50/50 TFMCB Water/Glycol 50/50 TFMCB 0 30.0 30.0 30.0 30.0 100 35.8 13.1 36.8 37.9 200 40.3 12.8 42.0 35.5 300 43.6 12.8 46.0 31.8 400 46.1 12.8 49.2 30.6 500 48.0 12.8 51.7 30.3 600 49.5 12.8 53.6 30.3 700 50.5 12.8 55.1 30.3 800 51.4 12.8 56.3 30.3 900 52.0 12.8 57.2 30.3

Example 10 Two Phase Immersion Cooling Application Using TFMCB in a Data Center

An example of data center cooling is provided, making reference to FIG. 9. A data center, generally denoted 200, includes a plurality of electronic subsystems 220 contained in one or more of electronics racks 210. At least one, and preferably a plurality, and preferably all, of the electronic subsystems 220 are associated with a cooling station 240 that includes (in one embodiment) a vertically-extending, liquid-to-air heat exchanger 243 and supply and return ducting 241, 242 for directing a cooling airflow 244 across liquid-to-air heat exchanger 243. A cooling subsystem 219 is associated with at least one, and preferably a plurality, and preferably all, of the multiple electronic subsystems 220. In a preferred embodiment, as shown in FIG. 9, all of the subsystem 220 are associated with the cooling station 240 and a cooling subsystem 219. Each cooling subsystem 219 comprises (in this embodiment) a housing 221 (which preferably is a low pressure housing) which encloses a respective electronic subsystem 220 comprising a plurality of electronic components 223. The electronic components are in operation as part of the data center and are generating as a result of performing their function in the data center. The components include, by way of example, printed circuit boards, microprocessor modules, and memory devices. Each electronic subsystem has, as it is operating, its heat generating components immersed in a thermal management fluid of the present invention 224. The fluid 224 boils in typical operation, generating dielectric vapor 225 according to the present invention. In the illustrated embodiment, electronic subsystems 220 are angled by providing upward-sloped support rails 222 within electronics rack 210 to accommodate the electronic subsystems 220 at an angle. Angling of the electronic subsystems as illustrated facilitates buoyancy-driven circulation of vapor 225 between the cooling subsystem 219 and the liquid-to-air heat exchanger 243 of the associated local cooling station 240. However, the excellent results according to the present invention and the present example rare achieved equally well when such angling is not used. Multiple coolant loops 226 are coupled in fluid and thermal contact with the liquid-cooled electronic subsystems and a respective portion of liquid-to-air heat exchanger 243. In particular, multiple tubing sections 300 pass through liquid-to-air heat exchanger 243, which in this example includes a plurality of air-cooling fins 310. Vapor 225 is buoyancy-driven from housing 221 to the corresponding tubing section 300 of liquid-to-air heat exchanger 243, where the vapor condenses and is then returned as liquid to the associated liquid-cooled electronics subsystem. Cooling airflow 244 is provided in parallel to the supply ducting 241 of multiple local cooling stations 240 of data center 200, and the heated airflow is exhausted via return ducting 242. The equipment as described herein, but not the fluid of the present invention, is disclosed in US 2013/0019614, which is incorporated herein by reference.

The system as describe above is operated with a thermal management fluid consisting of TFMCB and ambient air as the heat sink for the condenser, and this system operates to effectively, efficiently, safely and reliably maintain the electronic components in the most desired operating temperature range while the system is performing its function in the operating data center.

ASPECTS

The invention will now be illustrated by reference to the following numbered embodiments. The subject matter of the numbered embodiments may be additionally combined with subject matter from the description or from one or more of the claims.

Numbered Embodiment 1

A heat transfer composition comprising: (a) a refrigerant component comprising at least about 50% by weight of 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB) based on the weight of the refrigerant component.

Numbered Embodiment 2

The heat transfer composition of Numbered Embodiment 1 wherein the refrigerant component comprises TFMCB in an amount of at least about 50 wt % based on the weight of the refrigerant component.

Numbered Embodiment 3

The heat transfer composition of Numbered Embodiments 1 or 2 wherein the refrigerant component comprises TFMCB in an amount of at least about 70 wt % based on the weight of the refrigerant component.

Numbered Embodiment 4

The heat transfer composition of Numbered Embodiments 1 to 3 wherein the refrigerant component comprises TFMCB in an amount of at least about 90 wt % based on the weight of the refrigerant component.

Numbered Embodiment 5

The heat transfer composition of Numbered Embodiments 1 to 4 wherein the refrigerant component comprises TFMCB in an amount of at least about 95 wt % based on the weight of the refrigerant component.

Numbered Embodiment 6

The heat transfer composition of Numbered Embodiments 1 to 5 wherein the refrigerant component comprises TFMCB in an amount of at least about 99 wt % based on the weight of the refrigerant component.

Numbered Embodiment 7

The heat transfer composition of Numbered Embodiments 1 to 6 wherein the refrigerant component consists essentially of TFMCB.

Numbered Embodiment 8

The heat transfer composition of Numbered Embodiments 1 to 7 wherein the refrigerant component consists TFMCB.

Numbered Embodiment 9

The heat transfer composition of Numbered Embodiments 1 to 8 wherein the heat transfer composition further comprises a lubricant.

Numbered Embodiment 10

The heat transfer composition of Numbered Embodiment 9 wherein the lubricant is present in the heat transfer composition in an amount of from about 5% to about 30% by weight of heat transfer composition.

Numbered Embodiment 11

The heat transfer composition of Numbered Embodiment 9 or 10, wherein the lubricant is selected from the group consisting of Polyol Esters (POEs), Poly Alkylene Glycols (PAGs), PAG oils, polyvinyl ethers (PVEs), and poly(alpha-olefin) (PAO) and combinations thereof.

Numbered Embodiment 12

The heat transfer composition of Numbered Embodiment 11, wherein the lubricant is a POE or PVE.

Numbered Embodiment 13

The heat transfer composition of Numbered Embodiment 11, wherein the lubricant is a POE.

Numbered Embodiment 14

The heat transfer composition of Numbered Embodiment 11, wherein the lubricant is a PVE.

Numbered Embodiment 15

The heat transfer composition of any one of Numbered Embodiments 1 to 14 where the heat transfer fluid additionally comprises one or more co-fluids selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, trans-HFO-1336mzz, HF-1234yf, HFO-1234ze(E), HFO-1233zd(E) and HFO-1233zd(Z).

Numbered Embodiment 16

The heat transfer composition of any one of Numbered Embodiments 1 to 14 where the heat transfer fluid additionally comprises one or more co-fluids selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, methanol, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, HFO-1233zd(E), HFO-1233zd(Z).

Numbered Embodiment 17

The heat transfer composition of Numbered Embodiments 15 to 16, wherein the one or more co-fluids is present in the heat transfer fluid in an amount of at least about 5% by weight of heat transfer composition.

Numbered Embodiment 18

The heat transfer composition of Numbered Embodiments 15 to 16, wherein the one or more co-fluids is present in the heat transfer fluid in an amount of at least about 10% by weight of heat transfer composition.

Numbered Embodiment 19

The heat transfer composition of Numbered Embodiments 15 to 18,

wherein the heat transfer composition consists essentially of TFMCB and the one or more co-fluids.

Numbered Embodiment 20

The heat transfer composition of Numbered Embodiments 15 to 18,

wherein the heat transfer composition consists of TFMCB and the one or more co-fluids.

Numbered Embodiment 21

The heat transfer composition of any one of Numbered Embodiments 1 to 20 where the heat transfer composition is a class 1 heat transfer fluid.

Numbered Embodiment 22

The heat transfer composition of any one of Numbered Embodiments 1 to 21 where the heat transfer composition is a Class A refrigerant.

Numbered Embodiment 23

The heat transfer composition of any one of Numbered Embodiments 1 to 22 where the heat transfer composition is a class A1 refrigerant.

Numbered Embodiment 24

The heat transfer composition of any one of Numbered Embodiments 1 to 22 where the heat transfer composition has a Global Warming Potential (GWP) of not greater than about 1000.

Numbered Embodiment 25

The heat transfer composition of any one of Numbered Embodiments 1 to 23 where the heat transfer composition has a Global Warming Potential (GWP) of not greater than about 700.

Numbered Embodiment 26

The heat transfer composition of any one of Numbered Embodiments 1 to 23 where the heat transfer composition has a Global Warming Potential (GWP) of not greater than about 500.

Numbered Embodiment 27

The heat transfer composition of any one of Numbered Embodiments 1 to 23 where the heat transfer composition has a Global Warming Potential (GWP) of not greater than about 300.

Numbered Embodiment 28

The heat transfer composition of any one of Numbered Embodiments 1 to 23 where the heat transfer composition has a Global Warming Potential (GWP) of not greater than about 150.

Numbered Embodiment 29

A method for cooling a heat generating component in an operating electronic device, said electronic device comprising a thermal management fluid comprising TFMCB in thermal contact therewith, the method comprising transferring heat generated by the electronic device during operation to the thermal management fluid by vaporizing said thermal management fluid.

Numbered Embodiment 30

The method of Numbered Embodiment 29 wherein the thermal management fluid comprises TFMCB in an amount of at least about 5 wt. % of the thermal management fluid.

Numbered Embodiment 31

The method of Numbered Embodiment 29 wherein the thermal management fluid comprises TFMCB in an amount of at least about 15 wt. % of the thermal management fluid.

Numbered Embodiment 32

The method of Numbered Embodiment 29 wherein the thermal management fluid comprises TFMCB in an amount of at least about 50 wt. % of the thermal management fluid.

Numbered Embodiment 33

The method of Numbered Embodiment 29 wherein the thermal management fluid comprises TFMCB in an amount of at least about 70 wt. % of the thermal management fluid.

Numbered Embodiment 34

The method of Numbered Embodiment 29 wherein the thermal management fluid comprises TFMCB in an amount of at least about 90 wt. % of the thermal management fluid.

Numbered Embodiment 35

The method of Numbered Embodiment 29 wherein the thermal management fluid comprises TFMCB in an amount of at least about 95 wt. % of the thermal management fluid.

Numbered Embodiment 36

The method of Numbered Embodiment 29 wherein the thermal management fluid comprises TFMCB in an amount of at least about 99 wt. % of the thermal management fluid.

Numbered Embodiment 37

The method of Numbered Embodiment 29 wherein the thermal management fluid consists essentially of TFMCB.

Numbered Embodiment 38

The method of Numbered Embodiment 29 wherein the thermal management fluid consists of TFMCB.

Numbered Embodiment 39

The method of any one of Numbered Embodiments 29 to 36 where the thermal management fluid additionally comprises one or more co-fluids selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, trans-HFO-1336mzz, HF-1234yf, HFO-1234ze(E), HFO-1233zd(E) and HFO-1233zd(Z).

Numbered Embodiment 40

The method of any one of Numbered Embodiments 29 to 36 where the thermal management fluid additionally comprises one or more co-fluids selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, methanol, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, HFO-1233zd(E), HFO-1233zd(Z).

Numbered Embodiment 41

The method of any one of Numbered Embodiments 39 to 40 wherein the one or more co-fluids is present in an amount of at least about 5% by weight of the thermal management fluid.

Numbered Embodiment 42

The method of any one of Numbered Embodiments 39 to 40 wherein the one or more co-fluids is present in an amount of at least about 10% by weight of the thermal management fluid.

Numbered Embodiment 43

The method of any one of Numbered Embodiments 39 to 42 wherein the thermal management fluid consists essentially of the TFMCB and the one or more co-fluids.

Numbered Embodiment 44

The method of any one of Numbered Embodiments 39 to 42 wherein the thermal management fluid consists of the TFMCB and the one or more co-fluids.

Numbered Embodiment 45

The method of any one of Numbered Embodiments 29 to 44 where the thermal management fluid is a class 1 refrigerant.

Numbered Embodiment 46

The method of any one of Numbered Embodiments 29 to 45, wherein the thermal management fluid is a class A refrigerant.

Numbered Embodiment 47

The method of any one of Numbered Embodiments 29 to 46 where the thermal management fluid is a class A1 refrigerant.

Numbered Embodiment 48

The method of any one of Numbered Embodiments 29 to 47 where the thermal management fluid has no flash point.

Numbered Embodiment 49

The method of any one of Numbered Embodiments 29 to 48 where the thermal management fluid has a flash point of above about 100° F. (37.8° C.).

Numbered Embodiment 50

The method of any one of Numbered Embodiments 29 to 49, wherein said thermal management fluid is an electrically insulating thermal management fluid.

Numbered Embodiment 51

The method of any one of Numbered Embodiments 29 to 50 where the thermal management fluid has a Global Warming Potential (GWP) of not greater than about 1000.

Numbered Embodiment 52

The method of any one of Numbered Embodiments 29 to 50 where the thermal management fluid has a Global Warming Potential (GWP) of not greater than about 700.

Numbered Embodiment 53

The method of any one of Numbered Embodiments 29 to 50 where the thermal management fluid has a Global Warming Potential (GWP) of not greater than about 500.

Numbered Embodiment 54

The method of any one of Numbered Embodiments 29 to 50 where the thermal management fluid has a Global Warming Potential (GWP) of not greater than about 300.

Numbered Embodiment 55

The method of any one of Numbered Embodiments 29 to 50 where the thermal management fluid has a Global Warming Potential (GWP) of not greater than about 150.

Numbered Embodiment 56

The method of any one of Numbered Embodiments 29 to 55, wherein

the thermal management fluid is in direct contact with the heat generating component.

Numbered Embodiment 57

The method of any one of Numbered Embodiments 29 to 56 where the heat generating component is immersed in the thermal management fluid.

Numbered Embodiment 58

The method of any one of Numbered Embodiments 29 to 57, wherein said step of transferring heat from the heat-generating component to the thermal management fluid causes the thermal management fluid to vaporize.

Numbered Embodiment 59

The method of any one of Numbered Embodiments 29 to 58, wherein said thermal management fluid is circulated passively in said device.

Numbered Embodiment 60

The method of any one of Numbered Embodiments 29 to 58, wherein said thermal management fluid is circulated actively in said device, for example by using mechanical equipment such as a pump.

Numbered Embodiment 61

The method of any one of Numbered Embodiments 29 to 60, wherein the heat generating component is selected from semiconductor integrated circuits (ICs), electrochemical cells, power transistors, resistors, and electroluminescent elements, such as microprocessors, wafers used to manufacture semiconductor devices, power control semiconductors, electrical distribution switch gear, power transformers, circuit boards, multi-chip modules, packaged or unpackaged semiconductor devices, semiconductor integrated circuits, fuel cells, lasers (conventional or laser diodes), light emitting diodes (LEDs), and electrochemical cells, e.g. used for high power applications such as, for example, hybrid or electric vehicles.

Numbered Embodiment 62

The method of any one of Numbered Embodiments 29 to 61 wherein said electronic device is selected from personal computers, microprocessors, servers, cell phones, tablets, digital home appliances (e.g. televisions, media players, games consoles etc.), personal digital assistants, Datacenters, hybrid or electric vehicles, batteries both stationary and in vehicles, wind turbine, train engine, or generator, preferably wherein the electronic device is a hybrid or electric vehicle.

Numbered Embodiment 63

A electronic device comprising the thermal management fluid as defined any one of Numbered Embodiments 29 to 55.

Numbered Embodiment 64

The electronic device of Numbered Embodiment 63, comprising a heat generating component.

Numbered Embodiment 65

The electronic device of Numbered Embodiment 64, wherein the heat generating component is selected from semiconductor integrated circuits (ICs), electrochemical cells, power transistors, resistors, and electroluminescent elements, such as microprocessors, wafers used to manufacture semiconductor devices, power control semiconductors, electrical distribution switch gear, power transformers, circuit boards, multi-chip modules, packaged or unpackaged semiconductor devices, semiconductor integrated circuits, fuel cells, lasers (conventional or laser diodes), light emitting diodes (LEDs), and electrochemical cells, e.g. used for high power applications such as, for example, hybrid or electric vehicles.

Numbered Embodiment 66

The electronic device of any one of Numbered Embodiments 63 to 65, comprising at least one heat exchanger.

Numbered Embodiment 67

The electronic device of any one of Numbered Embodiments 63 to 66, comprising a means for actively circulating the thermal management fluid, such as a pump.

Numbered Embodiment 68

The electronic device of any one of Numbered Embodiments 63 to 67, wherein said electronic device is selected from personal computers, microprocessors, servers, cell phones, tablets, digital home appliances (e.g. televisions, media payers, games consoles etc.), personal digital assistants, datacenters, hybrid or electric vehicles, batteries both stationary and in vehicles, wind turbine, train engine, or generator, preferably wherein the electronic device is a hybrid or electric vehicle.

Numbered Embodiment 69

The use of a thermal management fluid as defined in any one of Numbered Embodiments 29 to 55 for cooling a heat-generating component in an electronic device as defined any one of Numbered Embodiments 56 to 62.

Numbered Embodiment 70

A process for converting thermal energy to mechanical energy in a Rankine cycle, the method comprising the steps of i) vaporizing a working fluid with a heat source and expanding the resulting vapor, then ii) cooling the working fluid with a heat sink to condense the vapor, wherein the working fluid is a heat transfer composition as defined in Numbered Embodiments 1 to 28.

Numbered Embodiment 71

A process for converting thermal energy to mechanical energy in a Rankine cycle, the method comprising the steps of i) vaporizing a working fluid with a heat source and expanding the resulting vapor, then ii) cooling the working fluid with a heat sink to condense the vapor, wherein the working fluid comprises at least about 50% by weight of TFMCB.

Numbered Embodiment 72

A process for converting thermal energy to mechanical energy in a Rankine cycle, the method comprising the steps of i) vaporizing a working fluid with a heat source and expanding the resulting vapor, then ii) cooling the working fluid with a heat sink to condense the vapor, wherein the working fluid comprises TFMCB with the proviso that the working fluid is not an azeotrope which is an admixture of about 21 to 27 weight percent TFMCB, 64 to 72 weight percent trans-1,2-dichloroethylene and about 5 to 11 weight percent methanol and the working fluid is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol.

Numbered Embodiment 73

The process of Numbered Embodiment 72, wherein the working fluid comprises at least about 50% by weight of TFMCB.

Numbered Embodiment 74

The process of Numbered Embodiment 72, wherein the working fluid comprises at least about 70% by weight of TFMCB.

Numbered Embodiment 75

The process of Numbered Embodiment 72, wherein the working fluid comprises at least about 80% by weight of TFMCB.

Numbered Embodiment 76

The process of Numbered Embodiment 72, wherein the working fluid comprises at least about 90% by weight of TFMCB.

Numbered Embodiment 77

The process of Numbered Embodiment 72, wherein the working fluid consists essentially of TFMCB.

Numbered Embodiment 78

The process of Numbered Embodiment 72, wherein the working fluid consists of TFMCB.

Numbered Embodiment 79

The process of any one of Numbered Embodiments 1 to 8 where the working fluid additionally comprises one or more co-fluids selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, trans-HFO-1336mzz, HF-1234yf, HFO-1234ze(E), HFO-1233zd(E) and HFO-1233zd(Z).

Numbered Embodiment 80

The process of any one of Numbered Embodiments 1 to 8 where the working fluid additionally comprises one or more co-fluids selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, methanol, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, HFO-1233zd(E), HFO-1233zd(Z).

Numbered Embodiment 81

The process of Numbered Embodiments 79 to 80, wherein the one or more co-fluids is present in the working fluid in an amount of at least about 5% by weight of working fluid.

Numbered Embodiment 82

The process of Numbered Embodiments 79 to 80, wherein the one or more co-fluids is present in the working fluid in an amount of at least about 10% by weight of working fluid.

Numbered Embodiment 83

The process of Numbered Embodiments 79 to 82,

wherein the working fluid consists essentially of TFMCB and the one or more co-fluids.

Numbered Embodiment 84

The process of Numbered Embodiments 79 to 82, wherein the working fluid consists of TFMCB and the one or more co-fluids.

Numbered Embodiment 85

The process of any one of Numbered Embodiments 79 to 84 where the working fluid is a class 1 refrigerant.

Numbered Embodiment 86

The process of any one of Numbered Embodiments 79 to 85 wherein the working fluid is a class A refrigerant.

Numbered Embodiment 87

The process of any one of Numbered Embodiments 71 to 86 where the working fluid is a class A1 refrigerant.

Numbered Embodiment 88

The process of any one of Numbered Embodiments 71 to 87 where the working fluid has a Global Warming Potential (GWP) of not greater than about 1000.

Numbered Embodiment 89

The process of any one of Numbered Embodiments 71 to 87 where the working fluid has a Global Warming Potential (GWP) of not greater than about 700.

Numbered Embodiment 90

The process of any one of Numbered Embodiments 71 to 87 where the working fluid has a Global Warming Potential (GWP) of not greater than about 500.

Numbered Embodiment 91

The process of any one of Numbered Embodiments 71 to 87 where the working fluid has a Global Warming Potential (GWP) of not greater than about 300.

Numbered Embodiment 92

The process of any one of Numbered Embodiments 71 to 87 where the working fluid has a Global Warming Potential (GWP) of not greater than about 150.

Numbered Embodiment 93

The process of Numbered Embodiments 71 to 92, wherein the mechanical work is transmitted to an electrical device such as a generator to produce electrical power.

Numbered Embodiment 94

The process of Numbered Embodiments 71 to 93, wherein the heat source is provided by a thermal energy source selected from industrial waste heat, solar energy, geothermal hot water, low pressure steam, distributed power generation equipment utilizing fuel cells, prime movers, or an internal combustion engine.

Numbered Embodiment 95

The process of Numbered Embodiments 71 to 94, wherein the heat source temperature is from about 90° C. to >800° C.

Numbered Embodiment 96

The process of Numbered Embodiments 71 to 95, wherein the heat source temperature is from about 400° C. to 800° C.

Numbered Embodiment 97

The process of Numbered Embodiments 71 to 96, wherein the heat source temperature is from about 400° C. to 600° C.

Numbered Embodiment 98

The process of Numbered Embodiments 79 to 97, wherein the heat source temperature is at least about 200° C., for example of from about 200° C. to about 400° C.

Numbered Embodiment 99

An organic Rankine cycle comprising a working fluid as defined in Numbered Embodiments 71 to 92 or a heat transfer composition as defined in aspects 1 to 28.

Numbered Embodiment 100

A high temperature heat pump comprising a heat transfer composition as defined in aspects 1 to 28.

Numbered Embodiment 101

A high temperature heat pump comprising a refrigerant, wherein the refrigerant comprises TFMCB, with the proviso that the refrigerant is not an azeotrope which is an admixture of about 21 to 27 weight percent TFMCB, 64 to 72 weight percent trans-1,2-dichloroethylene and about 5 to 11 weight percent methanol and the refrigerant is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol.

Numbered Embodiment 102

The high temperature heat pump of Numbered Embodiment 101, wherein the refrigerant comprises at least about 50% by weight of TFMCB.

Numbered Embodiment 103

The high temperature heat pump of Numbered Embodiment 101, wherein the refrigerant comprises at least about 70% by weight of TFMCB.

Numbered Embodiment 104

The high temperature heat pump of Numbered Embodiment 101, wherein the refrigerant comprises at least about 80% by weight of TFMCB.

Numbered Embodiment 105

The high temperature heat pump of Numbered Embodiment 101, wherein the refrigerant comprises at least about 90% by weight of TFMCB.

Numbered Embodiment 106

The high temperature heat pump of Numbered Embodiment 101, wherein the refrigerant consists essentially of TFMCB.

Numbered Embodiment 107

The high temperature heat pump of Numbered Embodiment 101, wherein the refrigerant consists of TFMCB.

Numbered Embodiment 108

The high temperature heat pump of any one of Numbered Embodiments 101 to 107 where the refrigerant additionally comprises one or more co-fluids selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, trans-HFO-1336mzz, HF-1234yf, HFO-1234ze(E), HFO-1233zd(E) and HFO-1233zd(Z).

Numbered Embodiment 109

The high temperature heat pump of any one of Numbered Embodiments 101 to 107 where the refrigerant additionally comprises one or more co-fluids selected from the group consisting of n-pentane, cyclopentane, cis-HFO-1336mzz, trans-HFO-1336mzz, HFO-1233zd(E), HFO-1233zd(Z) HFO-1234yf, HFO-1234ze(E).

Numbered Embodiment 110

The high temperature heat pump of Numbered Embodiments 108 to 109, wherein the one or more co-fluids is present in the refrigerant in an amount of at least about 5% by weight of refrigerant.

Numbered Embodiment 111

The high temperature heat pump of Numbered Embodiments 108 to 109, wherein the one or more co-fluids is present in the refrigerant in an amount of at least about 10% by weight of refrigerant.

Numbered Embodiment 112

The high temperature heat pump of Numbered Embodiments 108 to 111, wherein the refrigerant consists essentially of TFMCB and the one or more co-fluids.

Numbered Embodiment 113

The high temperature heat pump of Numbered Embodiments 108 to 111

wherein the refrigerant consists of TFMCB and the one or more co-fluids.

Numbered Embodiment 114

The high temperature heat pump of any one of Numbered Embodiments 101 to 113 where the refrigerant is a class 1 refrigerant.

Numbered Embodiment 115

The high temperature heat pump of Numbered Embodiments 101 to 114 wherein the refrigerant is a class A refrigerant.

Numbered Embodiment 116

The high temperature heat pump of any one of Numbered Embodiments 101 to 115 where the refrigerant is a class A1 refrigerant.

Numbered Embodiment 117

The high temperature heat pump of any one of Numbered Embodiments 101 to 116 where the refrigerant has a Global Warming Potential (GWP) of not greater than about 1000.

Numbered Embodiment 118

The high temperature heat pump of any one of Numbered Embodiments 101 to 116 where the refrigerant has a Global Warming Potential (GWP) of not greater than about 700.

Numbered Embodiment 119

The high temperature heat pump of any one of Numbered Embodiments 101 to 116 where the refrigerant has a Global Warming Potential (GWP) of not greater than about 500.

Numbered Embodiment 120

The high temperature heat pump of any one of Numbered Embodiments 101 to 116 where the refrigerant has a Global Warming Potential (GWP) of not greater than about 300.

Numbered Embodiment 121

The high temperature heat pump of any one of Numbered Embodiments 101 to 116 where the refrigerant has a Global Warming Potential (GWP) of not greater than about 150.

Numbered Embodiment 122

A method of heating a fluid or body using a high temperature heat pump, said method comprising the steps of (a) condensing a refrigerant as defined in Numbered Embodiments 101 to 120 in the vicinity of the fluid of body or be heated, and (b) evaporating said refrigerant.

Numbered Embodiment 123

The heat pump of Numbered Embodiment 100 to 121 or the method of Numbered Embodiment 122, wherein said heat pump is selected from a heat pump tumble drier, an industrial heat pump, a reversible heat pump, an air-to-air heat pump, a heat pump water heater or a high temperature water heater.

Numbered Embodiment 124

A secondary loop system comprising a heat transfer composition as defined in any one of Numbered Embodiment 1 to 28.

Numbered Embodiment 125

A secondary loop system comprising a primary refrigerant and a secondary refrigerant, wherein said secondary refrigerant is a heat transfer composition as defined in Numbered Embodiments 1 to 28.

Numbered Embodiment 126

The secondary loop system of Numbered Embodiment 125 wherein the secondary refrigerant comprises TFMCB in an amount of at least about 5 wt. % of the refrigerant.

Numbered Embodiment 127

The secondary loop system of Numbered Embodiment 125 wherein the secondary refrigerant comprises TFMCB in an amount of at least about 15 wt. % of the refrigerant.

Numbered Embodiment 128

The secondary loop system of Numbered Embodiment 125 wherein the secondary refrigerant comprises TFMCB in an amount of at least about 50 wt % of the refrigerant.

Numbered Embodiment 129

The secondary loop system of Numbered Embodiment 125 wherein the secondary refrigerant comprises TFMCB in an amount of at least about 70 wt % of the refrigerant.

Numbered Embodiment 130

The secondary loop system of Numbered Embodiment 125 wherein the secondary refrigerant comprises TFMCB in an amount of at least about 90 wt % of the refrigerant.

Numbered Embodiment 131

The secondary loop system of Numbered Embodiment 125 wherein the secondary refrigerant comprises TFMCB in an amount of at least about 95 wt % of the refrigerant.

Numbered Embodiment 132

The secondary loop system of Numbered Embodiment 125 wherein the secondary refrigerant comprises TFMCB in an amount of at least about 99 wt % of the refrigerant.

Numbered Embodiment 133

The secondary loop system of Numbered Embodiment 125 wherein the secondary refrigerant consists essentially of TFMCB.

Numbered Embodiment 134

The secondary loop system of Numbered Embodiment 125 wherein the secondary refrigerant consists of TFMCB.

Numbered Embodiment 135

The secondary loop system of any one of Numbered Embodiments 125 to 134 where the secondary refrigerant additionally comprises one or more co-fluids selected from the group consisting of HFE-7000, HFE-7200, HFE-7100, HFE-7300, HFE-7500, HFE-7600, trans-1,2-dichloroethylene, n-pentane, cyclopentane, ethanol, perfluoro(2-methyl-3-pentanone) (Novec 1230), cis-HFO-1336mzz, trans-HFO-1336mzz, HF-1234yf, HFO-1234ze(E), HFO-1233zd(E) and HFO-1233zd(Z).

Numbered Embodiment 136

The secondary loop system of any one of Numbered Embodiments 125 to 134 where the secondary refrigerant additionally comprises one or more co-fluids selected from the group consisting of n-pentane, cyclopentane, cis-HFO-1336mzz, trans-HFO-1336mzz, HFO-1233zd(E), HFO-1233zd(Z) HFO-1234yf, HFO-1234ze(E).

Numbered Embodiment 137

The secondary loop system of Numbered Embodiment 135 or 136, wherein the one or more co-fluids is present in an amount of at least about 5% by weight of the refrigerant.

Numbered Embodiment 138

The secondary loop system of Numbered Embodiments 135 or 136, wherein the one or more co-fluids is present in an amount of at least about 10% by weight of the refrigerant.

Numbered Embodiment 139

The secondary loop system of Numbered embodiments 135 to 138 wherein the secondary refrigerant consists essentially of the TFMCB and the one or more co-fluids.

Numbered Embodiment 140

The secondary loop system of Numbered Embodiments 135 to 138, wherein the secondary refrigerant consists of the TFMCB and the one or more co-fluids.

Numbered Embodiment 141

The secondary loop system of any one of Numbered Embodiments 125 to 140 where the secondary refrigerant is a class 1 refrigerant.

Numbered Embodiment 142

The secondary loop system of any one of Numbered Embodiments 125 to 141 where the secondary refrigerant is a class A refrigerant.

Numbered Embodiment 143

The secondary loop system of any one of Numbered Embodiments 125 to 142 where the secondary refrigerant is a class A1 refrigerant.

Numbered Embodiment 144

The secondary loop system of any one of Numbered Embodiments 125 to 143 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 1000.

Numbered Embodiment 145

The secondary loop system of any one of Numbered Embodiments 125 to 143 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 700.

Numbered Embodiment 146

The method of any one of Numbered Embodiments 125 to 143 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 500.

Numbered Embodiment 147

The secondary loop system of any one of Numbered Embodiments 125 to 143 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 300.

Numbered Embodiment 148

The method of any one of Numbered Embodiments 125 to 143 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 150.

Numbered Embodiment 149

The secondary loop system of Numbered Embodiments 124 to 148, wherein said system contains a primary vapor compression system loop that uses a primary refrigerant and whose evaporator cools a secondary loop fluid, wherein said refrigerant as defined in Numbered Embodiment 125 to 148 or heat transfer composition as defined in Numbered Embodiment 124 is used as the secondary loop fluid.

Numbered Embodiment 150

The secondary loop system of Numbered Embodiment 149, wherein said primary refrigerant is selected from the group consisting of HFO-1234ze(E), HFO-1234yf, propane, R455A, R32, R466A, R44B, R290, R717, R452B, R448A, and R449A, preferably HFO-1234ze(E), HFO-1234yf, or propane.

Numbered Embodiment 151

The secondary loop system of Numbered Embodiment 124 to 150, wherein said system is a secondary refrigeration loop system.

Numbered Embodiment 152

The secondary loop system of Numbered Embodiment 124 to 150, wherein said system is a secondary air conditioning loop system.

Numbered Embodiment 153

The secondary loop system of Numbered Embodiment 151, wherein said secondary refrigeration loop system is selected from a low temperature refrigeration system, a medium temperature refrigeration system, a commercial refrigerator, a commercial freezer, an industrial freezer, an industrial refrigerator and a chiller.

Numbered Embodiment 154

The secondary loop system of Numbered Embodiment 152, wherein said secondary air conditioning loop system is selected from a mobile air conditioning system, or a stationary air conditioning system.

Numbered Embodiment 155

The secondary loop system of Numbered Embodiment 154, wherein said stationary air conditioning system is selected from a chiller, particularly a positive displacement chiller, more particularly an air cooled or water cooled direct expansion chiller, which is either modular or conventionally singularly packaged, a residential air conditioning system, particularly a ducted split or a ductless split air conditioning system, a residential heat pump, a residential air to water heat pump/hydronic system, an industrial air conditioning system, a commercial air conditioning system, particularly a packaged rooftop unit and a variable refrigerant flow (VRF) system; and a commercial air source, water source or ground source heat pump system.

Numbered Embodiment 156

An automotive air conditioning system comprising a vapour compression system (the primary loop) and a secondary loop air conditioning system, wherein the primary loop contains HFO-1234yf as the refrigerant and the second loop contains a refrigerant of Numbered Embodiments 125 to 148 or a heat transfer composition of Numbered Embodiments 1 to 28.

Numbered Embodiment 157

The automotive air-conditioning system of Numbered Embodiment 156 where the secondary loop is used to cool a component in the car engine.

Numbered Embodiment 158

The automotive air-conditioning system of Numbered Embodiment 156 or 157 where the secondary loop is used to cool a battery.

Numbered Embodiment 159

A method of replacing an existing heat transfer fluid in a heat transfer system, said method comprising the steps of (a) removing at least a portion of said existing heat transfer fluid from said system, and subsequently (b) introducing into said system a heat transfer fluid comprising TFMCB in an amount of at least about 5 wt % of the heat transfer fluid.

Numbered Embodiment 160

The method of Numbered Embodiment 159 wherein the heat transfer fluid comprises TFMCB in an amount of at least about 15 wt % of the heat transfer fluid.

Numbered Embodiment 161

The method of Numbered Embodiment 159 wherein the heat transfer fluid comprises TFMCB in an amount of at least about 50 wt % of the heat transfer fluid.

Numbered Embodiment 162

The method of Numbered Embodiment 159 wherein the heat transfer fluid comprises TFMCB in an amount of at least about 70 wt % of the heat transfer fluid.

Numbered Embodiment 163

The method of Numbered Embodiment 159 wherein the heat transfer fluid comprises TFMCB in an amount of at least about 90 wt % of the heat transfer fluid.

Numbered Embodiment 164

The method of Numbered Embodiment 159 wherein the heat transfer fluid comprises TFMCB in an amount of at least about 95 wt % of the heat transfer fluid.

Numbered Embodiment 165

The method of Numbered Embodiment 159 wherein the heat transfer fluid comprises TFMCB in an amount of at least about 99 wt % of the heat transfer fluid.

Numbered Embodiment 166

The method of Numbered Embodiment 159 wherein the heat transfer fluid consists essentially of TFMCB.

Numbered Embodiment 167

The method of Numbered Embodiment 159 wherein the heat transfer fluid consists of TFMCB.

Numbered Embodiment 168

The method any one of Numbered Embodiments 159 to 167 where the heat transfer fluid is a class 1 refrigerant.

Numbered Embodiment 169

The method of any one of Numbered Embodiments 159 to 168 where the heat transfer fluid is a class A refrigerant.

Numbered Embodiment 170

The method of any one of Numbered Embodiments 159 to 169 where the secondary refrigerant is a class A1 refrigerant.

Numbered Embodiment 171

The method of any one of Numbered Embodiments 159 to 170 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 1000.

Numbered Embodiment 172

The method of any one of Numbered Embodiments 159 to 170 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 700.

Numbered Embodiment 173

The method of any one of Numbered Embodiments 159 to 170 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 500.

Numbered Embodiment 174

The method of any one of Numbered Embodiments 159 to 170 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 300.

Numbered Embodiment 175

The method of any one of Numbered Embodiments 159 to 170 where the secondary refrigerant has a Global Warming Potential (GWP) of not greater than about 150.

Numbered Embodiment 176

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing at least 5 wt % of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 177

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing at least 10 wt % of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 178

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing at least 15 wt % of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 179

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing at least 50 wt % of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 180

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing at least 70 wt % of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 181

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing at least 90 wt % of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 182

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing at least 95 wt % of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 183

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing at least 99 wt % of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 184

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing at least 99.5 wt % of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 185

The method of any one of Numbered Embodiments 159 to 175 where step (a) involves removing substantially all of the existing heat transfer fluid from said system, prior to step (b).

Numbered Embodiment 186

The method of any one of Numbered Embodiments 159 to 185 where the method comprising the step of flushing said system with a solvent after conducting step (a) and prior to conducting step (b).

Numbered Embodiment 187

The method of any one of Numbered Embodiments 159 to 186 where the heat transfer fluid replaces an existing fluid in an electronic device.

Numbered Embodiment 188

The method of any one of Numbered Embodiments 159 to 186 where the heat transfer fluid replaces an existing fluid in an Organic Rankine cycle.

Numbered Embodiment 189

The method of any one of Numbered Embodiments 159 to 186 where the heat transfer fluid replaces an existing fluid in a high temperature heat pump. Numbered Embodiment 190

The method of any one of Numbered Embodiments 159 to 186 where the heat transfer fluid replaces an existing fluid in secondary loop. 

1. A method for cooling a heat generating component that is operating in an electronic device, said method comprising: (a) operating said electronic device; (b) providing a thermal management fluid comprising 1-trifluoromethyl-1,2,2-trifluorocyclobutane (TFMCB) in thermal contact with the heat generating component of said operating electronic device; and (c) transferring heat from said operating, heat-generating component to said thermal management fluid by thermal contact with said TFMCB.
 2. The method of claim 1, wherein the thermal management fluid is in direct contact with the heat generating component and wherein said step of transferring heat comprises vaporizing said TFMCB or adding sensible heat to said TFMCB, or a combination of these.
 3. The method of claim 1, wherein the thermal management fluid consists essentially of TFMCB.
 4. The method of claim 1, wherein the thermal management fluid comprises at least about 50% by weight of TFMCB.
 5. The method of claim 1, wherein said TFMCB is at a temperature greater than about 55° C. during said transferring step (c).
 6. The method of claim 1, wherein the thermal management fluid has a dielectric constant of less than 30 and an electrical conductivity of less than 15 nS/cm.
 7. The method of claim 1, wherein the heat generating component is selected from semiconductor integrated circuits (ICs), electrochemical cells, power transistors, resistors, and electroluminescent elements, such as microprocessors, wafers used to manufacture semiconductor devices, power control semiconductors, electrical distribution switch gear, power transformers, circuit boards, multi-chip modules, packaged or unpackaged semiconductor devices, semiconductor integrated circuits, fuel cells, lasers (conventional or laser diodes), light emitting diodes (LEDs), and electrochemical cells, e.g. used for high power applications such as, for example, hybrid or electric vehicles.
 8. The method of claim 1, wherein said electronic device is selected from personal computers, microprocessors, servers, cell phones, tablets, digital home appliances (e.g. televisions, media players, games consoles etc.), personal digital assistants, Datacenters, batteries both stationary and in vehicles, hybrid or electric vehicles, wind turbine, train engine, or generator.
 9. The method of claim 8, wherein the electronic device is a hybrid or electric vehicle.
 10. A heat transfer composition comprising TFMCB.
 11. A process for converting thermal energy to mechanical energy in a Rankine cycle, the method comprising the steps of i) vaporizing the heat transfer composition of claim 1 as working fluid with a heat source and expanding the resulting vapor, then ii) cooling the working fluid with a heat sink to condense the vapor, wherein the working fluid comprises at least about 50% by weight of TFMCB.
 12. A high temperature heat pump comprising the heat transfer composition of claim 1 as a heat transfer fluid, wherein the heat transfer fluid comprises TFMCB, with the proviso that the heat transfer fluid is not an azeotrope which is an admixture of about 21 to 27 weight percent TFMCB, 64 to 72 weight percent trans-1,2-dichloroethylene and about 5 to 11 weight percent methanol and the heat transfer fluid is not an azeotropic composition which is an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent methanol or an admixture of about 82 to 92 weight percent TFMCB and about 8 to 18 weight percent ethanol.
 13. A secondary loop system comprising the heat transfer composition of claim 1 as a refrigerant comprising TFMCB.
 14. The heat transfer composition of claim 10, further comprising a lubricant.
 15. The heat transfer composition of claim 14, wherein the lubricant comprises at least one of a polyol ester (POE), a polyvinyl ether (PVE), and a polyalkylene gloycol (PAG).
 16. A method of replacing an existing refrigerant in a heat transfer system, said method comprising the steps of: (a) removing at least a portion of said existing refrigerant from said system and subsequently; (b) introducing into said system the heat transfer composition of claim 1 as a refrigerant comprising TFMCB.
 17. A method for removing heat from an article, device or fluid comprising: (a) providing a high temperature heat source which is generating heat at a temperature above about 70° C.; and (b) removing heat from said high temperature heat source by thermal contact with TFMCB liquid, wherein the temperature of said TFMCB liquid is above about 55° C.
 18. The method of claim 17, wherein said heat transfer fluid comprises at least about 50% by weight of TFMCB.
 19. The method of claim 17, wherein said heat transfer fluid is a non-flammable heat transfer fluid consisting essentially of TFMCB and having a dielectric constant of less than 30 and an electrical conductivity of less than 15 nS/cm.
 20. The method of claim 17 wherein said step of removing heat comprises vaporizing said TFMCB or adding sensible heat to said TFMCB, or a combination of these. 